A habit you'll want to get into

If there's one thing you really want to get into a bad habit of doing, that would be ensuring you check your mirrors regularly and relevantly depending on the circumstances.
Just brisk looks to ensure your brain is supplied with all the information you need to make an informed decision is all that is necessary. But not checking them will end up putting you and other road users in danger.
Just one missed mirror at the wrong time could end in being the worst choice you make.