roach motel

noun3

1. •
   A cockroach trap.
2. •
   (slang, figurative) Something that is easy to enter, but is difficult or costly to leave.

   • 8.3.1 The Importance of Easy Access: Avoid the “Roach Motel!” In Chapter 6, we discussed what a “roach motel” was. You can get data into a “roach motel”, but you can't easily get it out. — 2010
3. •
   (slang) a cheap hotel for people traveling by car, so dirty and badly kept that staying there is awful