I recall some Boeing data, several years ago, which showed a cyclic pattern to 757 tailstrikes. IIRC this was against fleet flight-hours which at that time equated roughly to a two and a half year period. Boeing were investigating reasons for this, some of which were that pilots progress through the industry, training programs evolved to match new priorities, and that humans (management, training and crews) forget the context or priority of safety initiatives.
I have seen and generated similar safety data which showed a cyclic pattern. Patterns probably can be found in any data, but with some circumstantial correlation from the items above, I wonder if there are any other safety patterns or studies which might help the safety of our industry.
The items all appear to be aspects of change, thus is the pattern a function of change management?