Prolly because Sungwoo always feel he got much more than he deserved as a gardener...the amout of salary and living in the mansion, and then he himself is the one who offers he wants to be more useful and "special" to Leo....so Leo basically just goes along and said "well, you're already enough, but if u want to be more special you can prove yourself"
Tbh I don't really see what the fuss is about with Leo's attitude in the comments below since for now he and Sung woo are still in employer-employee relationship..it's pretty reasonable
If I remember it right, the whole working at summer break was just a trial, to feel if he really wants to. I think that's already long time to 'prove' himself. Now there's this showdown, that's just Sungwoo being desperate to be more than 'special'.
Well Leo was already suspish in the first place but he's straightforward on wanting SW to be his gardener, only gardener. Him accepting that 'challenge' was just for his self-interest but really it wasn't necessary.
He's too openminded. When did he even owe them something? He's too accepting about it without asking important questions, are you really that bored of normal life, Sungwoo? Just give us the sad backstory, this is not masterchef flowers edition (〜￣△￣)〜