why some buyer don:t give feedback

[kevinstuff2012]

it is a choice or they have too left one?

[toby_le_pue]

Same reason some sellers don't leave feedback.

Feedback is not compulary

[kevinstuff2012]

That's not a reason because some seller's wait to received a feedback to send one.
Because to leave a feedback you need to know if your customer is fatisfied with the item first.