The importance of motivation in accomplishment can't be stressed enough.
In our society where the prevailing wisdom is that you are born with talent and if you don't magically find something easy you shouldn't waste your time — laziness and lack of success are the norm.
In our society, simply waking up, arriving at a job, going through the motions and going home is considered some sort of badge of honor as if you've accomplished something special by being able to put in the absolute minimum amount of effort to be alive.
Were you in the world of our ancestors where there was no society around you to make you Big Macs and coffee, you'd be a corpse. Well, you'd be in pieces from a pack of hyenas — regardless, the result would be the same.
Sadly, people bring these "success skills" to their automotive hobby and wonder why they fail. Simply put, the amount of effort you put into life doesn't even begin to match the amount of effort you need to. Successful people don't achieve their success by being "naturals," they achieve it through ridiculously high amounts of effort. Striving, driving, pushing — constantly — to be better.
Your car hobby requires nothing less.
Think about it, if you want to restore a car, you are looking at needing to achieve proficiency in not just one trade, but many. You need to be educated, and that education isn't gained by staring at your car or blindly tearing into it without a careful, detailed, plan — and that careful, detailed plan is based on that education that you lack.
I understand that your car hobby isn't a job, it's a recreational pastime, but it's a pastime built on the foundation of motivation and accomplishment you bring from the other parts of your life, and if you don't have it there, you aren't going to magically find it in the glove box of your disintegrating Camaro.
Basically, success in any endeavor starts with you, and if you haven't learned success skills, and are passionate about improving those skills, you will have nothing to bring to a hobby that requires a great deal of motivation to achieve success. Essentially, just like money can breed more money, success can breed more success, but if you don't manage your success correctly, just like your money, you lose it and there you are, picking through the disassembled parts of a rusted-out Buick like a washed up, broke rockstar trying to re-arrange the shattered pieces of his life.