Quite often and/or in a consistent, regular manner. The general manager drops into the restaurant on a regular basis, so the staff members have to be on their toes at all times.

Not very often and/or in an inconsistent, irregular manner. The general manager drops into the restaurant on a pretty irregular basis, so the members of staff tend to be pretty laid back here.

So familiar or friendly with someone as to be comfortable referring to them by their first name (as opposed to being more formal and using their surname). Don't worry, we'll get in—I'm on a first-name basis with the owner of the club. Wow, since when are you on a first-name basis with a famous author?