Fix the checkout before anything else
Users in your checkout have already decided to buy. Every one you lose there is a customer you paid to acquire and then dropped for a reason that is usually fixable. That makes checkout the highest-value surface on the site by a wide margin, and it is consistently the least examined because it is the hardest part of the stack to change.
The failures we find are concrete and unglamorous. Shipping cost revealed after the payment form, when it should be visible from the cart. A required account creation step between the cart and the purchase. Address validation that rejects legitimate international formats. A payment iframe that reflows on mobile and pushes the submit button off screen. An error state that clears the entire form. Each of these is measurable in the funnel data once the funnel data is trustworthy.
- Surface total cost including shipping and tax before the payment step
- Offer genuine guest checkout, not an account form labeled as guest
- Preserve form state through validation errors and back-navigation
- Support autofill, digital wallets, and mobile keyboard types correctly
- Make error messages specific and adjacent to the field that failed
- Test the full checkout on real iOS and Android devices, not desktop emulation
