10 UI Mistakes That Are Costing You Clients (And How to Fix Them)

The gap between looking good and converting well

Most redesigns we audit aren't ugly — they're just not doing their job. A site can look polished in a portfolio screenshot and still lose the visitor within seconds, because looking good and guiding someone toward a decision are two different skills.

The mistakes below show up again and again across otherwise well-designed sites. None of them are exotic. That's exactly why they're so easy to miss.

The mistakes we see most often

These are the patterns that quietly cost the most conversions, roughly in order of how often we catch them during an audit:

• Low-contrast text that reads fine to the designer, not the visitor
• Too many competing calls to action above the fold
• Inconsistent spacing that makes a page feel unfinished
• Load times over 3 seconds on mobile
• Navigation that hides the one page visitors actually came for

Fixing them without a full redesign

None of these require starting over. Most are targeted fixes — a contrast pass, a single clear CTA per section, a performance sprint — that can be shipped in days, not months. Start with whichever mistake is costing you the most traffic, not the one that's easiest to fix.