出落 is almost always used in praise - typically of a young woman who has grown up beautifully. Standard pattern:
出落得 + adjective phrase ('has grown up to be ___'). Common collocations:
出落得亭亭玉立 (grown into graceful elegance),
出落成大姑娘 (grown into a fine young lady). Don't use it for boys or for ordinary maturation - it's specifically about visible blossoming.
