How do you balance making an app look polished without hurting button responsiveness?

Built some really sleek page loading transitions recently that got great feedback on Twitter. But once real users got their hands on it they complained that navigating the app felt laggy.

People were trying to complete tasks quickly, and waiting even a quarter-second for a modal to fade in was frustrating them. Stripping out the extra motion effects instantly fixed the issue and made the product feel much faster to use.

Have you ever had to drop fancy UI animations after realizing they were just annoying your actual users?