To add detail onto my reply to your other comment then: these things are the things I hate about exercising outside! The sun is too hot, the wind is too cold.

To add detail onto my reply to your other comment then: these things are the things I hate about exercising outside! The sun is too hot, the wind is too cold. The puddles are a twisted ankle just waiting to happen. I don't want people to see me running - it makes me self conscious of every part of my body and my running form. I don't want to check the little free library during my exercise - that's a break in my flow. On a machine, I don't have to worry about any of that. I just go, and when I reach my time goal, or I don't feel like it anymore, I stop. I can close my eyes if I want to without worrying about falling over. I can make all the exertion noises I want to if it's hard. I don't have to walk all the way home if I go too hard too early by mistake and get a stitch. And the best bit is that your way and my way are both totally valid ways of exercising. The important bit is not how we exercise, the important bit is that we exercise.