Couples often ask me if a rehearsal is necessary. It depends.
For an elopement or very small, informal ceremony, a rehearsal is not necessary. We can do a 'run-through' just prior to the ceremony itself if need be. I always help you figure out who stands where, how close to each other, etc. whether or not we do a 'run-through' of the ceremony.
If your wedding has bride's maids and groomsmen, then absolutely YES, a rehearsal is necessary! Everyone needs to know where to stand, how to get there and when/how to leave and where to meet up for photos. Flower carriers and ring-bearers also need to practice, especially if they're young children. A couple of practice walk-throughs also makes a big difference in everyone's confidence the day of your ceremony and helps everyone relax and enjoy it more.
Rehearsals are typically like herding cats. Sometimes they are my favorite part of the process. No one knows what to do and most of the time everyone is happy to see friends and family they haven't seen for a long time. Lots of chatting and socializing going on. We do eventually get down to business and everyone ends up having a good time.
Aunt Carey wasn't at the rehearsal......