Congrats TS... stick with it.
The other day I put my own stripe on my belt, and the teacher got pissed. Why is he upset about this?
not this again.
I was curious about that too. After looking around, it seems the criteria varies among those that do award stripes; Since not everyone does this.
The most common seems to be for good attendance and/or progress over the number of months involved. Like most ranking systems that use them, I surmise it is mostly just a carrot i.e. a way to encourage you to keeping going.