I think the most common criticism laid at Schubert's feet or simply reason he’s not a favorite is that his music often feels too repetitive, to lost in itself and drown out beyond any tension he creates can be sustained. That despite his great capacity for melody and sadness the structures and figerations underlying these things are dull and uncreative. (Schumann said of Schubert's last sonatas that they ""ripple along from page to page as if without end,")

And while this criticism is relevant it really misses what Schubert was going for in his work.

Schubert (like Bach I think) didn't write music intending to end a piece or to reach a climax and resolve accordingly (preferably in a timely fashion), I think he was aiming to relay a kind of memory or feeling where the music passes like impressions of time pasts where pleasant memories fade suddenly into starkly melancholy ones. And viewing Schubert's use of form and repetition, of odd key relations and unorthodox modulations this way make much more sense and really helps realize that these traditionally negative traits give his music a tenderness that none else has achieved; and op 142 is a beautiful example of that style.

And since summer’s here and I have way too much time on my hands here's brief descriptions of all 4.

No 1 in F minor. This set of 4 is often cited as what's basically a 4 movement f minor sonata (beginning and ending in f minor) and though this makes sense I feel Schubert labeled them “Impromptus” (if in fact he did) to avoid any of the structural/temporal limitations of classic sonata form which clearly gave him pain in his early sonatas. But anyway this first impromptu is one of the most dramatic of the set with a first theme depending on how it’s played could sound vicious and menacing or anguished and moan-full that continues to interrupt the dreamlike (and very long if the repeats are observed) middle section. This kind of unbalance really contributes to a sense of uneasiness and hesitation that otherwise couldn't have been achieved.

No 2 in A flat minor. This little piece is really mostly built off a theme so warm and touching I would still love it if the piece just ended after the first repeat but as Schubert often does (see D960) after the first repetition the theme comes back dramatically in forte and returns followed by a gently rolling trio. Easily my favorite piece of the set.

No 3 in B flat major. A set of variations on a somewhat residential sounding the that’s simplicity is really exploited in the variations which follow. They act in the style developed by Beethoven in the appassionata and op 111 where each variations note values are smaller than the last which gives the impression that each time the theme is presented it’s not only varied but exalted in a sense. The center point is the minor variation where the theme is shown to (apparently) have been written in a way that can be flipped on its head to give a much darker character.

No 4 in F minor. Probably the greatest of the set with keyboard writing as revolutionary as it is compelling, all the themes have a obsessive quality that really takes multiple listenings to make “sense” but boy is it awesome.

Franz Schubert 4 Impromptus, D. 899