This happened to me many years ago. In the wake of the '08 financial crisis, I'd lost my job abruptly and decided to go travelling.
I'd accumulated a balance that was fairly substantial for me at the time (on the order of $10-15k, IIRC) and had been struggling to make the payments. I'd probably been 2-3 months behind on multiple occasions over the course of a year or so when a letter appeared that essentially said "we don't like you and we're going to close your account and pass your debt to a collection agency. However, if you pay off a portion of your balance in 4 monthly payments, and don't miss any of those payment dates, we'll wipe the rest."
I don't recall exactly what the discount was, but it was very substantial. In total I only had to pay something like 30-40% of the balance that I owed, so it was a very good deal. I'm not normally one to skip out on my debts but this was a huge relief to have a chance to be free of that debt: I pulled a lot of strings to make those payments on time!
True to their word, they wiped my entire balance and closed my account, and I never heard from them again (nor any collection agencies).