Well! Are the architects agreeing with one another, or disagreeing? When is it valid to say - “no that’s not the best I can do, I’m starting all over” and when, “Enough’s enough. I have to say now that it’s as good as I’ll get it”.
Of course, both are in agreement. Both accord themselves the luxury of saying “It’s done when I say it’s done”. And both are conscious that there must come an end-point when you have to say"It’s time to move on to something else - this one’s gone as far as I can take it".
I think Maya Lin, the architect of the incredible Vietnam Monument in Washington DC, amongst other things, is more inclined to say - build on the ideas you already have rather than chucking out everything, whereas I think Norman Foster is happy to start again from scratch. Hey, whatever floats your boat.
Same with any pursuit in life. Writing songs/poems/stories? The endpoint has to be reached and the author has to be happy with it. Operating on someone’s brain? Piloting a spaceship? Cooking a meal? Compiling a photographic project? Usually in any pursuit there has to be either a desired or enforceable deadline - a cut-off point. So of course you do your very best in the time you have available.
Just like in life.