And yeah, there's also the simple fact that if you're trying to organize from a disorganized state it's harder than if you're falling into an organization that was partially provided to you, which, when I was a teenager and in my early 20s I was still taking classes and it was easier to turn my time into time slots
To be fair to yourself, you also probably had a little less pressure on your time and attention at that point in time.
And yeah, there's also the simple fact that if you're trying to organize from a disorganized state it's harder than if you're falling into an organization that was partially provided to you, which, when I was a teenager and in my early 20s I was still taking classes and it was easier to turn my time into time slots