Why is the fish served last when serving?

Eating fish means "more than a year" and "more auspicious days" Fish is served on the last dish, probably because guests will have leftovers after eating many dishes, that is to say, "leftover fish"-"leftover fish" on the one hand is a lucky draw of "more than one year, more than one day"!

On the other hand, it means that food is very rich, enough to eat, but not enough. I thought the same thing.