The guy who limps every single hand preflop is not playing a strategy. He just wants to see flops. His range is literally anything. Which means when he hits, he hits weird.

Why they do it

You've seen this guy. He limps UTG with 94 offsuit and flops two pair. It's not a trap - he just plays every hand and sometimes gets there. The mistake is adjusting your entire game around his one weird flop. He's still a limper. He's still losing long term.

The adjustment

Isolate him when you have a real hand. C-bet boards that miss random ranges - which is most boards. When he check-raises you, believe him. He got there again.

What it's worth

Consistent isolation of the table limper is one of the most reliable profit sources at $1/$2. Don't overthink it. Just be the one raising him instead of the one limping behind.