Examples of Bad Designs
ูุจู ู ุง ูุชุนูู ุงูุตุญุ ุฎูููุง ูุดูู ุงูุบูุท. ุงูุฏูุชูุฑ ุจูุฏู 7 ุฃู ุซูุฉ ู ู ุงููุงูุน.
CFC ู 457000 ุบูุฑ ู
ูุถุญุฉ. Not self-evident.Usability โ 3 Pillars
ุงูุชุนุฑูู ุงูุฑุณู ู ู ู ISO + ุงูู 3 ู ุนุงููุฑ: Effectiveness, Efficiency, Satisfaction.
โ ISO
"We can't predict a software system's usability without testing it with real users." โ Ferre et al., 2001
ุฏุฑุฌุฉ ูุฏุฑุฉ ุงูู system ุนูู ุชุญููู ุบุฑุถู: ูู ุงูู user ููุฏุฑ ูุฎูุต ุงูู ูู ุฉ ุจูุฌุงุญุ
ู ุซุงู: Banking app โ ูู ุงูู user ูุฏุฑ ูุญููู ูููุณ ุจุฏูู ู ุณุงุนุฏุฉุ ูุนู โ effective.
ุงูู user ุจูุฎูุต ุงูู ูู ุฉ ุจุณุฑุนุฉ ูุฏ ุฅูู ูุจู ุฌููุฏ ูููู ูุฏ ุฅููุ
ู ุซุงู: Banking app โ ุชุญููู ูููุณ ูู 2 clicks ุฃุญุณู ู ู 10 clicks. ุงูู 2 clicks ุฃูุชุฑ efficient.
ุฏุฑุฌุฉ ุฑุถุง ุงูู user ุนู ุงูุชุฌุฑุจุฉ. ุจุชุชูุงุณ ุจุงูู feedback ุฃู surveys.
ู ุซุงู: ูู ุงูุชุทุจูู intuitiveุ ุฌู ูู ุจุตุฑูุงูุ ู easy to navigate โ ุงูู user ุฑุงุถู.
Why Usability Matters
ุฏูุฑ ุงูู ุทูุฑ ยท Common pitfalls ยท Business impact.
ุชุตู ูู software ูุชูุงูู ู ุน ุงุญุชูุงุฌุงุช ูุชููุนุงุช ุงูู ุณุชุฎุฏู ูู.
Usability ูุญุดุฉ โ users ุบูุฑ ุฑุงุถูู โ ุฒูุงุฏุฉ support costs โ ู ุนุฏู ุชุจูู ุฃูู.
Usable software โ user satisfaction ุฃุนูู โ retention ุฃุนูู โ ูุฌุงุญ ูู ุงูุณูู.
- Involvement in Design โ ุงูู Developers ูุดุงุฑููุง ุจุฏุฑู ูู ู ุฑุญูุฉ ุงูุชุตู ูู ุนุดุงู ูุฏู ุฌูุง ุงูู usability ู ู ุงูุจุฏุงูุฉ.
- Collaboration with Designers โ ุงูุชุนุงูู ู ุน UX/UI designers ุนุดุงู ูุญุตู alignment ุจูู ุงูุฃูุฏุงู ุงูุชูููุฉ ูุฃูุฏุงู UX.
- Iterative Development โ ุชุญุณููุงุช ุนูู ู ุฑุงุญู ู ุน continuous user feedback ู testing.
| ุงูู Pitfall | ุงูู description |
|---|---|
| Feature Creep | ุฅุถุงูุฉ features ูุชูุฑุฉ ุจุฏูู ุฏุงุนู โ ุงูู interface ู ุฒุฏุญู |
| Ignoring User Feedback | ุฅูู ุงู ุงุญุชูุงุฌุงุช ูุณููููุงุช ุงูู users ุงูุญูููููู |
| Overcomplicating Interfaces | ุชุตู ูู ุงุช ู ุนูุฏุฉ ุฌุฏุงู |
| Lack of Testing | ุงูุงุนุชู ุงุฏ ุนูู ุงูุชุฑุงุถุงุช ุงูู developers ุจุฏูู validation |
System Usability Scale (SUS) โญ
ุฃูู metric ูู ุงูู usability. ุณุคุงู Winter 2025 Q1.16 ูุงู ุนู ุญุณุงุจ SUSุ ููุชุนุฑู ุชุญุณุจู ููุง.
- Standardized questionnaire ูููุงุณ ุงูู usability.
- ุทููุฑู John Brooke ุณูุฉ 1986.
- ุงูุฃูุซุฑ ุงุณุชุฎุฏุงู ุงู ูู UX research.
- 10 questionsุ ุชูููู ู ู 1 (Strongly Disagree) ูู 5 (Strongly Agree).
| # | Question | Type |
|---|---|---|
| 1 | I think I would like to use this system frequently | + |
| 2 | I found the system unnecessarily complex | โ |
| 3 | I thought the system was easy to use | + |
| 4 | I think I would need the support of a technical person | โ |
| 5 | I found the various functions were well integrated | + |
| 6 | I thought there was too much inconsistency | โ |
| 7 | I would imagine that most people would learn this system very quickly | + |
| 8 | I found the system very cumbersome to use | โ |
| 9 | I felt very confident using the system | + |
| 10 | I needed to learn a lot of things before I could get going | โ |
- For odd questions (1, 3, 5, 7, 9): subtract 1 from user response.
- For even questions (2, 4, 6, 8, 10): subtract user response from 5.
- This scales all values from 0 to 4.
- Sum all 10 converted values (range 0 to 40).
- Multiply by 2.5 โ final score 0 to 100.
// For each odd question (Q1, Q3, Q5, Q7, Q9):
converted = response - 1
// For each even question (Q2, Q4, Q6, Q8, Q10):
converted = 5 - response
// Final score:
SUS = (sum of all converted values) ร 2.5
| Score | Grade | ุงูุชูุณูุฑ |
|---|---|---|
| 80.3+ | A | People love it & recommend it |
| โฅ 68 | C | Above average โ OK but can improve |
| ~ 68 | Avg | Average โ needs improvement |
| < 51 | F | Make usability priority NOW |
ุฌุฑุจ ุชุญุณุจ SUS ู ู ุฑุฏูุฏ ู ุณุชุฎุฏู ูุงุญุฏ. ุงูุฃุฑูุงู ู ู 1 (strongly disagree) ูู 5 (strongly agree):
- Quick & easy โ ุฏูุงูู ููููุฉ.
- Standardized and reliable.
- Widely accepted.
- Subjective โ ู ุจูู ุนูู ุงูุฅุฏุฑุงู ุงูุดุฎุตูุ ูู ู ูู ูุชุฃุซุฑ ุจุงูู ุฒุงุฌ ุฃู ุงูุฎุจุฑุฉ.
- Limited Granularity โ single score ุจุฏูู ุชูุงุตูู ุนู ุงูู ุดุงูู ุงูู ุญุฏุฏุฉ.
UMUX โ Usability Metric for User Experience
ุฏู ุดุจู shorter SUS: 4 ุฃุณุฆูุฉ ุจุณ ุจุฏู 10. ู ููุฏ ููู rapid prototyping.
- [This system's] capabilities meet my requirements.
- Using [this system] is a frustrating experience.
- [This system] is easy to use.
- I have to spend too much time correcting things with this system.
- ุฃูุตุฑ ู ู SUS (4 ุจุฏู 10 ุฃุณุฆูุฉ).
- Strong correlation with SUS โ ูู SUS ูุชุทูุน ูุฐุงุ UMUX ุบุงูุจุงู ูุชุทูุน ูุฑูุจุฉ ู ููุง.
- Easy & quick โ ู ุซุงูู ููู rapid prototyping ุฃู early-stage testing.
Nielsen's 10 Usability Heuristics โญ
Jakob Nielsen ุณูุฉ 1994. ุฏู ุฃุดูุฑ 10 guidelines ูุชูููู ุงูู UIุ ููุงุฒู ุชุญูุธูู ุจุฃู ุซูุฉ.
Accessibility โ Definition (ISO)
ุงููุฑู ุจูู Usability ู Accessibility: ุงูู Usability ุจุชุชููู ุนู specified usersุ ููู ุงูู Accessibility ุชุณุชูุฏู ุฃูุณุน ูุทุงู ู ู ูู.
โ ISO
Targeting specified users in a specified context.
ู ุซุงู: app ูู ุญุงุณุจูู ุงูุดุฑูุงุช โ ุงูู usability ุจุชููุณ ูุฏ ุฅูู ุงูู ุญุงุณุจูู ุจูุณุชุฎุฏู ูู ุจุณูููุฉ.
ุงุณุชูุฏุงู widest range ู ู ุงูู users ุจู ุฎุชูู ุงููุฏุฑุงุช ูุงูุธุฑูู.
ู ุซุงู: ููุณ ุงูู app โ ูู ููุฏุฑ ุฃุนู ู ูุณุชุฎุฏู ู ุจู screen readerุ ูู ููุฏุฑ ุดุฎุต ุนูุฏู ุฅุนุงูุฉ ุญุฑููุฉ ูุณุชุฎุฏู ู ุจููุจูุฑุฏ ุจุณุ
POUR โ 4 Legal Requirements โญ
Accessibility Regulations 2018 ูู UK Public Sector: 4 ุดุฑูุท ุนุดุงู ุงูู ููุน ุฃู ุงูุชุทุจูู ูุจูู accessible.
ุงูู ุนููู ุงุช ูุงูู UI components ูุงุฒู ุชููู ูุงุจูุฉ ููุฅุฏุฑุงู ุจุงูุญูุงุณ (ุจุตุฑุ ุณู ุนุ ูู ุณ) ุจุบุถ ุงููุธุฑ ุนู ูุฏุฑุงุช ุงูู ุณุชุฎุฏู .
- Text Alternatives โ ูู image ุชููู ุนูุฏูุง
alttag ููู screen readers.<img src="search.png" alt="Search button"> - Color Contrast โ high contrast ุจูู ุงููุต ูุงูุฎูููุฉ ูู color-blind users.
- Audio Content โ captions ุฃู transcripts ููู video/audio ููู deaf/hard-of-hearing.
ุงูู interface ูุงุฒู ุชููู ูุงุจูุฉ ููุชุดุบูู ุจู ุฎุชูู ูุณุงุฆู ุงูุฅุฏุฎุงู: keyboard, mouse, touch, voice.
- Keyboard Accessibility โ ูู function ู ุชุงุญุฉ ุจุงูู keyboard (Tab + Enter).
- Touchscreen Support โ buttons ูุจูุฑุฉ ููุงูุฉ ูู ุชุจุงุนุฏุฉ ููู motor impairments.
- Avoid Time Limits โ ุฃู ููุฑ ุฎูุงุฑ ูุชู ุฏูุฏ ุงูููุช.
ุงูู ุญุชูู ูุงูุชุดุบูู ูุงุฒู ูููููุง ูุงุถุญูู ูุณูู ููู ูู ุ ุญุชู ููู cognitive disabilities ุฃู ุฃุตุญุงุจ limited tech knowledge.
- Easy Language โ Enter your email ุจุฏู Please provide your contact information.
- Predictable Navigation โ ุงูู menu ูู ููุณ ุงูู ูุงู ุนูู ูู ุตูุญุฉ.
- Form Field Labels โ ูู field ุนูุฏู label ูุงุถุญ.
ุงูู system ูุงุฒู ูููู ู ุชูุงูู ู ุน ู ุฎุชูู assistive technologies ู ุซู screen readers ู voice recognition.
- ูุดุชุบู ุนูู desktop ู mobile.
- ูุฏุนู browsers ู ุฎุชููุฉ.
- ูุดุชุบู ู ุน JAWS, NVDA, VoiceOver.
Inclusive Computing
ุชุตู ูู technology ูุฃูุณุน ูุทุงู ู ู ูู ู ู ุงููุงุณ. 15% of global population = 1 ู ููุงุฑ ุดุฎุต.
๐ง Cognitive
Dyslexia, learning disabilities
๐๏ธ Sensory
Vision, hearing impairments
โฟ Physical
Motor impairments, wheelchair users
๐ฃ๏ธ Language
Non-native speakers
๐ Cultural
Different backgrounds
๐ฐ Socioeconomic
Income, education differences
- 15% of global population ุนูุฏูู ุดูู ู ู ุฃุดูุงู ุงูุฅุนุงูุฉ.
- ูู ุงูู tech ู ุด inclusive = 1 ู ููุงุฑ ุดุฎุต ู ุด ููุนุฑููุง ูุณุชุฎุฏู ูุง ุฃุฏูุงุชูุง.
- Inclusivity โ better innovation. ูู ุง ุชุตู ูู ููุฌู ูุนุ ุจุชุฏูุน ุญุฏูุฏ ุงูู tech.
- ุงูู Speech recognition systems ุบุงูุจุงู ุจุชุชุฏุฑุจ ุนูู standard speech.
- ุงููุงุณ ุงููู ุนูุฏูู speech impairments ู ุง ููุฏุฑูุด ูุณุชููุฏูุง ูููุณ.
- Project Euphonia ุจูุฏุฑูุจ AI ุนูู non-standard speech.
- ุจูุญุณูู ูุฏุฑุฉ ุงูู voice recognition ูุฏุนู ุงูู accessibility.
- Guillermo Robles โ ุฃุนู ูุ ู ุง ูุฏุฑุด ูุณุชุฎุฏู Domino's website/app ุจู screen reader.
- Domino's: ุญุฌุชูุง ุฅู ูุงููู ADA (1990) ู ุง ุจูุบุทูุด ุงูุฅูุชุฑูุช.
- U.S. Supreme Court: ุฑูุถุช ุงูุญุฌุฉ. ุงูู ADA applies to digital platforms.
- ุงูุฏุฑุณ: ุงูู Digital accessibility = legal requirement ู ุด ุงุฎุชูุงุฑ.
- Recognize Exclusion โ ุงุนุฑู ุงูู bias ูุงูู exclusions ุงููู ุจุชุญุตู ุจุณุจุจ mismatch ุจูู ุงููุงุณ ูุงูุชุฌุฑุจุฉ.
- Learn from Diversity โ ุงูู Inclusive Design ุจูุญุท ุงููุงุณ ูู ุงูู ุฑูุฒ. perspectives ู ุชููุนุฉ = insights ุญููููุฉ.
- Solve for One, Extend to Many โ ุงูุชุตู ูู ููู permanent disabilities ุจููุชุฌ ุญููู ุชููุน ุงูุฌู ูุน.
| Feature | ูููุงุณ ู ุน |
|---|---|
| Screen Reader Support (JAWS/NVDA + alt text) | Visual impairments |
| Keyboard Navigation (Tab key access to all elements) | Motor impairments |
| Color Contrast & Text Size | Low vision, color blindness |
| Captions & Transcripts | Hearing impairments |
Exam Question Bank โ Lecture 7
8 ุฃุณุฆูุฉ ู ู ุงูุงู ุชุญุงูุงุช ุงูุญููููุฉ. SUS, Nielsen, Accessibility ูููู ู ุชูุฑุฑูู.
Q1=4, Q2=2, Q3=5, Q4=2, Q5=4, Q6=2, Q7=5, Q8=2, Q9=5, Q10=1
What is the SUS score?
= (4โ1) + (5โ1) + (4โ1) + (5โ1) + (5โ1) = 3+4+3+4+4 = 18
Even questions (Q2, Q4, Q6, Q8, Q10): 5 โ response
= (5โ2) + (5โ2) + (5โ2) + (5โ2) + (5โ1) = 3+3+3+3+4 = 16
Sum = 34. ร 2.5 = 85.
ุงูู score > 80.3 โ grade A โ Excellent.
1. ๐ Bell with red badge (notification count)
2. ๐ Shopping cart with item count
3. Step progress indicator (Step 1 / Step 2 / Step 3 / Step 4)
4. ๐ Battery level indicator (50%)
- Bell + badge โ ุนุฏุฏ ุงูู unread notifications.
- Cart count โ ุนุฏุฏ ุงูู items ูู ุงูู cart.
- Step indicator โ ุงุญูุง ูู ุฃู ุฎุทูุฉ ู ู ุงูู flow.
- Battery โ ู ุณุชูู ุงูุจุทุงุฑูุฉ ุงูุญุงูู.
โข Use understandable encoding techniques
โข Ensure users can always get out, go back, or undo actions
โข Ensure the sequence of actions to do a task is as simple as possible
โข Ensure that the UI's appearance is uncluttered
- Home + Cancel + Next = ุงูู user ููุฏุฑ ูุฎุฑุฌุ ููุบูุ ุฃู ููู ู (User Control & Freedom).
- Universal icons ููุชุงุฑูุฎ ูุงูุฏุฑุฌุฉ ูุงูุฑูุงุจ (Understandable encoding).
- Clean layout ุจุฃูุณุงู ู ููุตูุฉ (Uncluttered).
Cheat Sheet
SUS formula ยท Nielsen 10 ยท POUR ยท ISO definitions.
๐งฎ SUS Scoring Formula
๐ Nielsen 10 Heuristics
โฟ POUR Accessibility
๐ ISO Definitions
๐จ Famous Names
๐ฏ UMUX (shorter SUS)
Rapid Revision
Flashcards ยท Common Mistakes ยท What the doctor loves.
๐จ Common Mistakes
โญ What Dr. El-Ramly Loves
- SUS calculation โ ุจูุฏู 10 responses ููุทูุจ ุงูู score. ุงุญูุธ ุงูู formula ูููุณ.
- Nielsen heuristic violated โ ุจูุฏู screenshot ูู bad UI ููุณุฃู ุฃู rule ุจูุฎุงูู.
- Encoding techniques โ universal icons.
- Accessibility definition โ ุงูููู ุฉ ุงูู ูุชุงุญูุฉ "widest range".
- POUR โ ูู principle ู ุฑุชุจุท ุจู ุซุงู (alt text = perceivable, keyboard = operable).
- System status icons โ ุฃู ุซูุฉ (battery, notifications, progress).