1- First looking at a way to try new calibers for a lot cheaper than a new Ruger, Remington, Savage, CZ, etc...
2- Thinking I would have an out of the box, simple ,MOA shooter......then the frusteration of finding out that these rifles have a catch, you have to learn how to shoot them. After buying a 223 Ultra for cheap fun, then seeing the potiential these rifles have, and learning that shooting them well is difficult-the learning cure wasn't going to beat me. Call me stubborn.
3-Keep buying them because they are inexpensive, very accurate, and simple/rugged.