The problem is cognitive load. I have to deal with 20 apps or websites, each has 5-10 non-text icons. I then have to drag my mouse over each icon and wait for the preprogrammed 1000ms timer to show me what the icon is actually doing, which I'll then forget by the time I next use your app. It's too much load, it's too much irritation waiting for your stupid 1000ms timer to fire. It makes me hate your app without consciously realizing why.