Having circled with a buddy adamant on parking in NYC, I can tell you that t works like this:

1. Circle
2. Circle
3. Spot open parking
4. Pull in, get out
5. Go to sign
6. Compare time of day, street side, date, weekday, car type, against sign
7. Discover on leap year even-date Tuesdays you can’t park a blue domestic car here unless your name is steve
8. Curse. GOTO 1