True story. When you are old enough to be a 40+ geezer like some of us on here, you find yourself going back and finishing promises you made to yourself or others when you were in your teens and twenties. At 40, you can feel intuitively how life is slipping away, time is speeding up logarithmically, and you don't have a lot of time to waste.

You remember this as being part of "self actualization" from Maslow's stuff that we all had to study and had no idea what it meant. I had no idea.

These were promises that were interrupted, there was no interest/no time/no money. Maybe these promises required you to have a certain skill. Maybe the people you promised are now either dead or dying. You will return to it if it's worth returning to and you will get a giant sense of fulfillment from making progress or completing, much more than your normal, contemporary goals.

For Spielberg, this was one of those moments. He did it because maybe he promised himself or his mother that he would finish. So, it means much, much more to him than one might think.