Your knowledge of history is flawed: there were no tapes at the Watergate hotel. The issue was an 18 minute gap in the White House taping system that was believed to be a discussion of a coverup concerning the Watergate breakin.
If memory serves me, the Watergate burglars used a strip of tape over the lock to keep the door from locking them inside, and the tape was noticed by a security guard, leading to their arrest.