A 2003 study found that more than a third of patients treated for rebound headaches from analgesics begin overusing that medication again within a year. This is greater than the percentage who return to using triptans or ergots.
Considering that painkillers are pretty effective when people first start taking them, this makes a lot of sense. Over time, they become less helpful and lull you into rebound. Sounds a lot like the trap of caffeine.