B2B permanent job?!

[WTFH]

Why do foriegn companies elect to go this route? Why not B2B direct with a contractor Ltd? They would have no liability for unpaid taxes should the contractor ltd fall foul of HMRC. Just seems to me like it would be simpler and cheaper to cut out the middle man. I bet there must be a reason, hopefully someone will explain.

Could be one of multiple reasons, but the more obvious ones involve the company not being purely focussed on UK contractors, and the UK definition of a contractor and will want to have a global policy that works no matter where a contractor is from.
Then there’s the idea of preferred suppliers. They don’t want to have to set up every single contractor as a supplier on their system.