I'd put it off, despite having active and accident-prone family members and living near a crash black spot.
Eventually I needed to do a course, for work, and went along expecting to be a little bored.
I wasn't bored, in fact it was fascinating. A lot has changed since I did first aid at college.
Two days later there was a crash outside my house. With "DRSABC" and "30 to 2 no matter who" still fresh in my mind I went through the drill.
Sadly, there was nothing I could do for the driver, who was killed instantly. But that drill stopped me from rushing about in a panic. I could check the other victims - all unhurt - and relay information to emergency services.
No, it was not ideal. But the security blanket of having done that course...priceless. I urge everyone who gets the chance - please, do a first aid course. You could save a life.