The phrase "mediocre results" means when the outcome or performance of something is not particularly good, but also not very bad either. It is average or ordinary, without being exceptional. Full definition
Given these feelings, administrative work is done without enthusiasm and often with mediocre results which serve to confirm the negative evaluation attached to this work at the outset. (religion-online.org)
That's why many smart guys get mediocre results. (greenbackd.com)
Our commitment to early childhood learning success will continue to produce mediocre results. (earlylearningfoundation.com)