So instead of filling in a simple form (and with many banks being paid to switch using the current account switching service), you'd rather:
Go in to a bank, withdraw all of your cash, close your account
Go to a new bank, open an account, pay your money in
Contact all businesses you have outstanding DDs with, and set up new ones.
Recreate all of your payees on your new banks online banking
Set up any standing orders again.