If you're on the fence about whether or not to hire someone to photograph your event, consider these reasons:

The event is a family reunion, and you want to get a group photo of the whole family. You could do it yourself, but one of two things could happen. You have someone take the picture for you, leaving a family member out of the image because they had to take it. This could offend that person or make them feel awkward about being excluded. Or you set a timer on your camera. This could be problematic because there are so many people in the photo that you will need to take several images to make sure everyone is looking and has their eyes open. You will have to take two to three times as long to get the photos done because you'll have to keep resetting the timer, and you still might not have gotten the shot. Hiring a professional will eliminate all of this stress.

I don't know about you, but I don't want to go around all night taking selfies with my phone or camera with all of my friends and family members. I prefer to relax and enjoy the moment instead of trying to capture it. The quality of the photos will be much better than the selfies. Also, trying to take a selfie with a group of people is next to impossible when getting everyone inside the frame.