We're talking about 2 different things here, squatters and deadbeat tenants. Squatters are those who move in uninvited and just take over the property. Deadbeats are those who rent a place and quit paying but don't leave. The problems are the same for landowners but in many cases the legal implications are quiet different.

The OP was about squatters, not deadbeats.

“In a time of deceit telling the truth is a revolutionary act.”
― George Orwell

It's not over when you lose. It's over when you quit.