Not speculation,but....
I was thinking along these lines a couple of days ago but did not post.
I do the pre-flight as best I can on the L4 and take my time ,a very simple craft although there are hidden cables for all the major controls.
We have the annual and 25 and 50 hr checks but some of these sytems will not be inspected for a whole year.
Not speculating on this accident,but it does make one think about what goes unckecked.
Lister