Lots of planes have minor problems, in fact, I suspect they all do to some extent or another.

One of the Avistar falvors is easy to assemble with an overly weak wing center that can fold in flight, but it's not really a fault of the design.

The Alpha occasionally has problems with the fuel tank stopper being too tight, and the nose strut likes to shed screws if they aren't locktited. Of course, most ARF trainers will shed the nose strut, I don't know if I've ever seen one installed with locktite.

Several Hobico trainers shared a commonly weak firewall that was only a matter of time until it came loose if you flew off of grass.

These are the ones I've seen first hand.

It wouldn't surprise me if the manufacturers have fixed some of these issues, and I'm sure there are lots more in planes I haven't mentioned.

YMMV. I wouldn't avoid any of the planes I mentioned above for the reasons mentioned. I would always check and double check anything pre-done at the factory before flight.