Let's say you want to make a game that's just a five minute rollercoaster ride in 3D.
If you imagine the most entertaining five minute rollercoaster ride you possibly can, and then make it, you can still chop it up into pieces afterwards, and give players the pieces, and then let them make their own rollercoaster rides out of those pieces by reconfiguring them in different ways.
Or, you could just make a bunch of pieces, and then attempt to put them together in the best way possible afterwards, and that'd let you try a bunch of different stuff and find a best solution for the pieces you have, and you might even think of something you wouldn't have thought of it you did it the other way.
Just like you might not think of something awesome you could do if you tried to do it brick by brick up instead of starting from the top and drilling down into the details, I mean, you aren't gonna think of something like a way to make a rollercoaster ride that actually makes fun of itself at certain points by doing it brick by brick.
But either way you make it, I don't wanna ride your rollercoaster more than a couple of times, tops, its doesn't matter how you do it, its ride once or twice and throw away, to me, 'cause I'm just a regular lazy bastard and I'm not really interested in trying to make my own rollercoaster out of all your stupid rollercoaster bits and pieces, I got other stuff to do.
That's what I'm paying you for, y'know, to figure it out.
And either you got something or you don't.
This is not one of those things where you can help me help myself heh.
And if you don't show me something good right off the bat, I definitely ain't gonna try it twice and then bring a friend to show it to a third time, so you ain't even gonna get that.