What Moon does in a chart
Moon is the part of the chart that answers one question:What do I need in order to feel safe? It describes emotional needs — not events, and not outcomes.
What Leo does to it
Leo is a fire sign, so it moves on impulse and enthusiasm. It is also fixed, which means it holds things. Put those together with Moon and you get needs warmth — warm, expressive, proud, applied specifically to emotional needs.
Leo is ruled by Sun, so this placement tends to be coloured by core identity as well.
The useful version
Placements are not verdicts. This one describes a default setting, not a limit — the things listed above are what you do when you are not thinking about it, which is exactly why noticing them is worth something.