kind of lacks development of any kind, not just an intro.
the sample is great and all and it's not bad that you repeated it the whole time, the main issue was that there were no distinguishable sections in the song. tension/build-up and release are and will always be a huge part of the way that people naturally listen to music, and it's important to keep that in mind when creating. this rule has proven true all through the history of music, from skrillex to scriabin.
i can tell you were gradually adding stuff on/switching it up every two bars, but there was no "story arc" in your music, and that's what really needs to be improved. people can talk shit all they want about your sample and your synth and your snares, but as long as you have solid development, it will always be good music.
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also, your melody can have as many notes as you want. the main section of wiz khalifa's black and yellow is literally three notes arpeggiated and we all know that's catchy as hell.
quality > complexity