I was going to be a Personal Trainer. I was going to pay my dues at a big box gym until I had the experience and clients to go off on my own and do what I wanted to do: Specialize in working with pregnant and post-partum women. I thought this was something that people really needed.
See, most easy-to-find personal trainers have never given birth to a child. If you walk into a gym in search for a personal trainer, or (in my personal experience) more commonly, when the person selling you the gym membership talks you into adding on a discounted training package and assigns you a trainer, your options are likely to consist primarily of young people really into standard forms of exercise and body building.