Say I have a phone whose security is corporately managed, and this management demands that I use a 6 digit passcode to lock the phone. So far, so reasonable. This gives an attacker a possibility of 1,000,000 passcodes to try if they were to brute force. The phone locks for 5 minutes every time the passcode is entered wrong, too.
However, if I am expected to never use any sequential or repeating numbers, surely this reduces the space of possible codes by a huge amount? Thus making the phone easier to break into. Why would this policy be used?