How much are you paying for a drill sergeant?
Perhaps you can burn 500 calories on the treadmill before you give up for the day. With a personal coach, though, you could do 700. The trainer gets you to exert more effort.
You wake up on a Monday morning after a long hard weekend of misbehaving. You have a splitting headache. You can easily call in sick, no one will freak out. But then you remember that there's a $500 bonus at stake if you keep your attendance perfect. You make the effort because someone else is bribing you.
On the playground, it's tempting to rip into a kid who stole the swing from you. You're about to whack him, but then you see your mom watching. With a great deal of effort, you walk away.
Effort's ephemeral, hard to measure and incredibly difficult to deliver on a regular basis. So we hire a trainer or a coach or a boss and give up our freedom and our upside for someone to whip us into shape. Obviously, you give up part of what you create to the trainer/coach/boss in exchange for their oversight.
Has it become a crutch? Are you addicted to a taskmaster, to someone else's to do list, to short term external rewards that sell your long-term plans short? If no one is watching, are you helpless, just a web surfing, time wasting couch potato? Who owns the extra work you do now that you're being directed?
There's an entire system organized around the idea that we're too weak to deliver effort without external rewards and punishment. If you only grow on demand, you're selling yourself short. If you're only as good as your current boss/trainer/sergeant, you've given over the most important thing you have to someone else.
The thing I care the most about: what do you do when no one is looking, what do you make when it's not an immediate part of your job... how many push ups do you do, just because you can?