Well, it took me years to build my shop in phases. And it became an end in itself, and a distraction from the things I really wanted it for. And I neglected the house, which is almost 200 years old, and was in need of few things.
So yes, there came a point where I was feeling a letdown, and I wasn't using my garage for the intended purposes, so it did seem a bit like, is that all there is ? Then of course I had to turn to the house, which meant more time away from the hobbies, cars and garage. But the garage was still there, and lo and behold, there was a space for cars, and a space for a wood shop, and a lot of storage. So I segued into actually using the shop to support my home restoration, and gradually found that I could also use the garage portion for larger car projects that could remain there uninterrupted for as long as it took me to get back to them.
So I have a 30X26 garage, a 22x26 woodworking shop, a 9x13 machine storage area, and a large second story studio. I could reconfigure it any time I want to, but from the outside it looks like an old fashioned barn with shed wings. And it ISN'T too big, and it WASN'T too much, and it Was Worth It in the long run.
Is that all there is ? No. There is life after your garage project is finished, no matter how long or how draining it may be. And after the let down, it sits there and abides, waiting for the day that you feel like doing something besides stuffing things in there.
What ever your dreams are, what ever you built it for, it can do all of those things, or more, whenever you get the notion. After I replaced the old sills in my house, and rewired the outer walls, insulated and installed the new back doors, I got sick of working on the house, and rebuilt a tired old convertible. When I had that running, I built a new deck off the back of my house. I then set up the wood shop to build the cabinets for my all new bathroom. Now I'm building cabinets for somebody else.
SO I'm off and running. Rome wasn't built in a day, and neither was my garage. But slow and steady wins the race, even if you take four left turns and get totally sidetracked on the way to places you never even thought of going. It's ALL good, once you figure out that it is all GOOD.