While some overseas rescues are very good (some of the breed specific ones, mostly) a lot of them seem completely shoddy and disorganised.
One couple I know, both with chronic health conditions which limited their physical acitivity, with two young DC (KS1 kind of ages), took on a huge young dog from Estonia or somewhere which looked like a flock guardian type. He was going to need very clued-on owners, plenty of exercise, and, at best, lots of supervision around the kids.
These people are not clued on about dogs, they would be unable to provide more exercise than a short toddle round the playing fields, and they hadn't the space to keep dog and DC apart.
The dog lasted with them about a month. Goodness knows where he ended up.
Net result? One very confused and unsettled dog into the UK's overloaded rescue system, two very naive but well-intentioned adults feeling like failures, and two upset kids.
Absolute idiocy on the part of the rescue, but the dog was off their books, so hey, all sunshine and roses from their POV.
The whole system needs proper regulation.