However from 14 onwards are all great (maybe exception of 16th)
I think the most underrated Mozart orchestral work is the 18th. That slow movement there is mindblowing and my personal favourite of his career.
In any case even if 11-13 were disappointing it produced the greatest quote by a musician ever where Mozart described his artistic aim of writing music that is within the golden mean of accessibility and intelligence and lamented how composers tries to achieve solely the former and solely the latter
"These concertos [Nos. 11, 12, and 13] are a happy medium between what is too easy and too difficult; they are very brilliant, pleasing to the ear, and natural, without being vapid. There are passages here and there from which the connoisseurs alone can derive satisfaction; but these passages are written in such a way that the less learned cannot fail to be pleased, though without knowing why. . . . The golden mean of truth in all things is no longer either known or appreciated. In order to win applause one must write stuff which is so inane that a coachman could sing it, or so unintelligible that it pleases precisely because no sensible man can understand it."