How do you balance a clean UI with making sure buttons are actually easy to understand?

I tried removing all text from our dashboard because we wanted that modern clutter free look.

But during user testing most people hovered over the same icon for ages or clicked the wrong thing entirely.

Adding just two words under each button completely fixed the problem and everyone breezed through the next test.

It made me realize how often we design for aesthetic screenshots instead of what users actually need. Have you run into this with your own apps?