Originally Posted by HillRider

"Crank retention problems" usually mean the crank arm itself is damaged. That is the square taper hole in it has been hogged out or distorted because the crank bolts (or nuts in this case) weren't torqued sufficiently tight and the arm moved on the spindle. The crank arms are aluminum and the spindle is hardened steel so guess which gets damaged? And, once this happens, the crank is not repairable by any reasonable method.

There is nothing inherently wrong with nutted bottom brackets although they tend to be cheaper, low-line ones. Installed properly and the nuts torqued sufficiently, they will hold the crank arms as reliably as any other type. That assumes the crank arm itself is in good condition.