It's not sugar that makes the tea sweet , it's the stirring.

[wowenglish1]

What does Charlotte mean by the next sentence?
It's not sugar that makes the tea sweet , it's the stirring.

Mikki : Where are you going?
Charlotte: To volunteer at the homeless shelter. Mikki.
Mikki: Does that make you happy?
Charlotte: It's not sugar that makes the tea sweet , it's the stirring.

 

[Chicken Sandwich]

NOT A TEACHER

I think that it's a metaphor. It's not the sugar (money) that makes the tea (work) sweet, it's the stirring (the fact that you're doing some good for mankind). In other words, Charlotte doesn't need to be remunerated. Doing some good for others is enough of a remuneration for her.