That...means more than what you might think.
The UI of a game is like his presentation. If the presentation is appealing, it will change the way you would see the game for the positive. Having a presentation that isn't appealing might do the opposite and that's really just a feeling you would maybe not pay attention to.
For example, it really was significant for me when I played melee which is my foundation of my gamers interest. The menu gave me the feeling I was in control of the game and it feels like I was inside a computer or the Gamecube itself and it has to do with the background and the C stick along with the form of the buttons. It felt like a printed circuit board when you would navigate in it. The sound effects also gave me this same feeling and all this resulted me that I wanted to use the menu and plsy just because it reminded me that I was in control of the game.
Not to mention the music that I could describe it by one words: universal. It felt like the experience wasn't just this game, but something more global.
It really was significant on how I viewed melee and it;s one of those reasons that it lead me to love video games in the first place because they are so well tough that it can be considered as an art.
Another one was TTYD. Not only the UI felt very true to the game having the paper as the theme, but also bright colors. The colors I love the most are the one that are very bright and my favourite being
Cyan green. I love also when the colors are unified meaning that it has practically no shade or has no transparency. Finally, I like better lines that are straight instead of curves since it seems simple and straight forward for me. Most of the UI and even the whole design of the game was exactly like that and I can tell you that it was VERY significant on my view of it. I became addicted mainly because of how it match those tastes perfectly and the UI being of course included.
You could put the same for wind waker since it had so much Cyan green that I just loved to press start.
Basically, the appearance of menus are quite important because you can be more tempted to use them and that's a big factor. Being encouraged to use them is like the game prompting you to play more as it is quite a big portion of the presentation.
It's like if I do an introduction in an essay, it has to be well written to make the essay interesting just by reading it which will make the essay encouraging to read. The opposite might not reflect the message of my essay if I want to deliver quality which will influence the way the reader see it. My presentation is always the music Earthbound Sanctuary Guardians as because I listened to it in loop while writing my essay, it reminds me to think carefully and the readers to consider carefully as it can be crucial in debate. That is my whole debate philosophy and I want to reflect this in my essay.
I told a lot, but some time, simple things are way deeper when you think about them.
EDIT: and you just got 10k posts, well, take it as a gift