>Prior to Generation V, TMs were single-use items, unlike Hidden Machines, which can be used over and over again on many different Pokémon. TMs can be found on the ground or bought at department stores.
So yes, in Pearl, Platinum, Diamond and all the previous games TMs were single use only before they went poof and broke
As to WHY they did that. You'll need to go ask Gamefreak that. I'd probably guess that since they weren't required to get through the game, Gamefreak decided to just make it a one time use only. But fans got pissed and they changed it. Maybe :D?
Lol I don't know actually. >.> The best we can do is make theories on it and hope for the best.