I sold a few shares when they were at 20 or some dollars a share thinking AMD would stay second fiddle to Intel for the rest of time. Turns out I am a terrible value investor.
I thought about buying them at under $2 a few years ago but didnt... I probably would have cashed out half my share at $8 or $15 thinking the catchup to Intel was temporary. I'm glad they are doing well. There is no perfect crystal ball.
Don't buy cheap stocks and hope they go up. Buy expensive stocks and watch them go up.