My Plugin has hard rejected


I have developed wordpress subscription plugin but it has hard rejected. I got following message

“Thank you for your submission. We have completed our review of “NMP Popup Exit” and unfortunately we found it isn’t at the quality standard required to move forward, and you won’t be able to re-submit this item again.”

I want to develop new plugin. can any one help me which techniques / standard should use to develop the plugin . I will be gratefull for your valuable help