I don't have citations so this is entirely armchair, but, a few hundred kcal under your maintenance is fine for weight loss, going too far below that is a crash diet; going back or above your maintenance needs then will lead to your body storing extra, because it believes times are bad.

One issue is that people go overboard with dieting, then any excess hits double. The other issue is that they go from one diet to the next, without ever establishing a stable baseline. You shouldn't try to lose weight if you don't even have a stable baseline yet.