A year ago this month I did 2 of my garages with a 2-part epoxy garage floor paint that was supposed to be great. My main reason for painting them was because they had been painted before, and needed it again (thatís one of the maintenance issues Jay J mentioned). There were 2 coats already down. Iím not sure how old, but the original owner had a Porsche in the middle 60ís, and there was a tell-tale oil stain on top of the first coat, from a car with a rear engine like a Porsche. The second coat was done after that, and came off almost completely when I was prepping for my new coat.
I did the directions to the letter, mixed the 2 cans, rolled it out, sprinkled the multi-colored texture stuff, and looked BEAUTIFULÖfor about a month.
That was when I first parked a car on it. The next day when the wife backed out the car, up came the paint with the tires. Interestingly enough, the original coat did not come up. I assume I did something wrong, but I canít figure it out. The brand, which had a picture of an armadillo on the box, was supposed to be fine with existing coats so long as the directions were followed. It was like $80.00 since I had to buy 2 mixtures for 2 garages.
Well, most of the floor still looks fine today since only 1 car uses these garages, and its tires hit the same general area each time.
So the bottom line is: surface prep is the key. And maybe it would be better to just clean the concrete since all the paints mention re-coating in 2-5 years.