Because of greed pure and simple.
I just bought a flat but was waiting on a confirmation. When we finally got it it was a rush to move and switch everything to a new flat. We had to give 6 weeks notice to our landlord fair enough he needs time to get someone to move in but with broadband there is zero excuse its not like the broadband needs someone else to take over the bill because the internet is constantly drained. Thames water british gas and eon do not require a notice period so bt do not have to do it but its a good way to screw people over. If you ask them why it takes 30 days to cancel the broadband it doesnt they will never tell you why they require notice because they don't its just a good way to keep you tied to them for another month
