It can be a slogan

for encouraging people when they are unhappy,

down or miserable.

Start From Zero was founded by a Hong Kong local street artist - Dom.

START stands for STreet ART, STencil ART and STicker ART.

 

The are two meanings of Start From Zero
 

He started performing street art from nothing, i.e. “zero; I hope that when someone see my stickers,

they will be like me, start doing street art from “zero”.

 

It can be a slogan for encouraging people when they are unhappy, down or miserable.

He also wants people to remind their friends of this slogan

when the same things happen.