I am 100% trad, 55 year of age and in the game 20 years now.
I've taken a handful of tumbles, every one of which has been down to user error. Fortunately not once have I been hurt, but I realize it could have been very different.
These days I take great care to ensure the ladders aren't going to slip before climbing them.
I believe accidents with ladders are caused by simply lacking due care and attention to the potential dangers of using them, beit by complacency or incompetence, or being insufficiently confident using them. That said, the ladders have to be fit for purpose in the first place.
I would say that the more you use them, the more complacent you can become, but to balance this out the less you use them, the more incompetent you can become, or you could become less confident using them.
Bottom line is, if you must use ladders, make sure you and they are up to the job.
John.