I read the About section before playing, so I was well aware of that being the only way to win. That has nothing to do with my criticism.
EDIT: Actually, the way you described it is pretty misleading. You said you have to finish EVERY level with 1 or 2 hearts, but really you only have to finish the last level. I thought I was screwing myself over by completing any level with 3 hearts, which is why I complained that the game gave no earlier indication of your failure. I didn't communicate this criticism very well I admit.