I thought I was done but no because I just realized
The ending of 8x10 basically confirms that Oliver fell in love with Felicity at first sight.
Not like we often think of “love at first sight” like you immediately know you’re in love with the person, but “love at first sight” in that...in retrospect, you realize that you started loving them the moment you first saw them.
Oliver has 20 years to craft a perfect moment for him to finally see Felicity again - and we see the evidence of his fine attention to detail. But when does he choose?
2x06, when he first realized he was probably in love with her?
No. What about 3x01, when he finally decides to go for it?
Noooo. How about 3x20, the first time she told him she loved him?
Nope. Also not 3x23, when he chose her:
And not beautifully idyllic Ivy Town either:
Not even his first proposal:
HE CHOOSES AN AMALGAMATION OF THE FIRST TIME HE EVER SAW HER (3x14 flashback) AND THE FIRST TIME HE EVER TALKS TO HER (1x03).
Because from the beginning, there was just something about her. His heart knew it all along. None of those other moments marks the first time he loved her, or when he loved her “most,” because he always loved her. Right from the start. There was never a moment when he didn’t already love her, which is why the moment he first saw her, and the moment he first spoke to her, remain the most significant moments in their history to him.