One thing I think is often neglected in motivation science is the immense value in failing. Ever since William James' initial writing on habit there has been this tacit belief that if you want to succeed at a habit you need to start hard and go hard forever, period, and if you stop, God help you. You’ve failed to build the habit. You’ve tainted your long term efforts.
What really happens is that if you come back to it a year later you have all sorts of knowledge from your first trial. You have reduced the uncertainty associated with the habit (and therefore its difficulty), have a rough idea of where it fits into your life, an awareness of how to do it, what the sticking points are, and so on. You also have confidence that you can sustain it for an extended period of time, because you already did, even if you didn’t manage to do it indefinitely. And you have a series of ideas about what you could optimize, to tailor the goal to your own unique personality and circumstances.
It’s a little bizarre because if you ask people what things they desperately wish they could have, going into a hard endeavor like learning to get in shape, the things they would tell you are things like "I wish it wasn’t so hard" or "I wish I knew in advance that this would work" or "I wish I knew how to fit this into my life instead of just figuring it out as I go" or "I wish I was more confident/certain in my ability to do this." People would pay for that stuff. They already do, by the boatload; that’s what the self help industry is.
And all of those are things that one good round of trying and failing will give you, for free. Two is even better. Three? Good god, you’re golden.
And yet we treat trying and failing like... failing.