Actually, never. Worked for one Megacorp for entire c@reer. BUT, it was not uncommon to be w*rking in one department, field, specialty, or location and with 15 minutes notice be informed that I was now reporting elsewhere (within the company). Could be worse, I suppose, but the disruption and looking forward to yet another learning curve was a significant stressor (not like being laid off or fired, though).
My favorite example was the time I was assigned to an area for which I was part-time teaching university courses in the field of w*rk involved. I was called into the boss' office and he hung his head. I knew this wasn't going to be a good day. He told me to report (tomorrow) to a new field in which I had once taken an "intro" course back in college. I had taken it only to fulfill an academic requirement. I had no interest and had shown little aptitude for the subject matter. Yet, I was to become the new "expert" in the area.
Fortunately, I never was in the military, but my experience reminded me of stories I often heard of the "military way" of filling positions. The guy who can type a 130 words per minute goes into the infantry because that's where they need a warm body at the time.
Ko'olau's Law -
Anything which can be used can be misused. Anything which can be misused will be.