Only time I've had one "break" on me was when Brawl came out. It was a common issue because Brawl was a dual layer disc, meaning it was harder for the laser to read the disc, and because my Wii was generally on the ground, it gathered more dust than normal, so after a few weeks, my Wii stopped reading Brawl, and for some reason, other games too. Had to send it in to Nintendo for them to replace the disc drive. Luckily, since it was a common issue, it was free.