A second default is a forecast, not a surprise.

Landlords tend to spend their worry on the first missed payment, which says very little, and not enough on the second, which says a great deal.

A first missed payment can mean almost anything. A second one, coming after a payment arrangement was agreed, means one thing fairly reliably: the arrangement was not affordable either. The tenant took on the old rent plus a slice of the arrears, and the sum did not fit. That turns the second default into a forecast, and a forecast is useful because there is still time to act on it. Waiting to be surprised again only adds arrears to a deposit that was never going to cover them.

The steps that follow are slow by design. A letter of demand has to give the tenant a fair chance to pay before the lease can be cancelled, and if the tenant stays after cancellation, only a court can order an eviction, which takes time and legal costs. So the landlord who starts after the second default is weeks ahead of one who waits for the fourth. It can also mean agreeing a moving date while both sides are still civil. Surprise, at that point, is a choice.