See, that’s a little bit vague. Anything I say as to what I think they mean will only be speculation. There are some songs I’ve heard on audiojungle.net that sound like they don’t meet the standards that they mention here, but those songs are approved, nonetheless. It would be a bit tacky for me to list examples of such, so just suffice to say that I’ve have heard stuff that didn’t sound to me like they were up to par.
Don’t feel bad, I submitted my first song 24 days ago and I already know it’s going to get tossed. I just hope they can explain in detail why.