i dont know anyone who skates exclusively transition.
what im wondering is, if you never leave the bowl/mini, when do you replace your deck and why?
when youre skating street or flat its easy to notice the sogging out or the loss of pop.
obviously you replace it when it legit breaks lol
For some people, boards can still get really flexi without breaking, so in that way it is not all that different, pumping in big transition and feeling the tail mush out sort of thing is a good reason to change out a board.
Really though, boards can last a whole lot longer on mini ramps without crazy big decker type tricks, which are often board breakers through the middle, but then I have also seen some amazingly bad chips from people trying airs or similar and bailing and unwittingly flinging the board, chipping up and then needing to be swapped out sooner rather than later.
The boards I keep just for my mini ramp really get paint wear and nothing else, so from that, it is more when I get sick of them and change them out than anything else, so I have some of those boards still going for years, compared to other boards I skate everything on and are done in a month or so.
Some of the guys I know who have Powell Flight boards change the grip every few months and maybe epoxy the dings and keep those things going longer than anyone else I know, which is nuts, but they hold up a long time for those transition / half pipe / vert dudes.