What are some overlooked UX issues that cause downstream support problems?

As we’ve talked to more Shopify merchants and DTC teams, one pattern keeps coming up, small UX issues at checkout or signup often turn into unexpected support tickets or operational costs.

Examples include:

Customers entering bad shipping info

Forgetting to update address after a move

Autocomplete inserting outdated or partial data

Ambiguous form layouts causing confusion

In many cases, these feel like minor friction points in the moment, but they lead to refunds, failed deliveries, or support load weeks later.

We’ve been exploring solutions for one piece of this puzzle related to addresses (we work on Address Validation iO), but we’re really curious what other subtle UX issues you've seen snowball into bigger problems.

What edge cases have caught you off guard? What fixes have actually worked for you?

Would love to learn from others and hear how you're tackling these quietly expensive mistakes.