I also get more structured workouts inside, where I'm able to follow my targeted power exactly, whereas outside things like hills, terrain, or stoplights can disrupt your plan. When I'm going down a hill in a virtual world, I can keep pedalling, whereas when I'm going down a hill in reality I run out of gears at 45mph, and have to slow down for the corners. I probably got 6k miles on my indoor trainer and those miles were all exactly the types of workout I had hoped for. It's also more convenient to ride in my basement or in my bedroom, while watching Netflix or listening to conference, and often with my family. Americans spend hours of time per day watching TV, and I try to spend those hours also on a bike in the same room as my family, which I couldn't do outside (at least for now where they aren't able to keep up outside).

Riding outside is better for my soul. It also feels just a little different ergonomically (the bike has more wiggle and you tend to get out of the saddle and rest a little more), and I think that leads to fewer injuries.