STEN was 2 Pounds, or $9, vs $45 for the M1 carbine or over $200 for the Tommy Gun.
M1 Carbine was accurate to 100M, while the STEN could hose 9mm to that distance, but not accurately. When it didn't jam.
Germans liked the M1 carbine, one of the few battlefield pickups besides the PPSh. STEN? Better than being unarmed.
That's a pretty low bar
Sten was select fire - no need to hose to 100m - you can plink to 100m
The best German soldier loved the Sten
And of course the Germans built it at the very end of the war
And not all Stens are created equally the early ones were spammed out by toy companies the later ones were of better quality and built by arms companies that used to be toy companies
The point of the Sten was that by 42 the British were able to dump 300 plus Sten guns on every battalion
What battalions would do is to test all the guns and send those that did not work well back to the factory and for those that were really bad (Friday afternoon made ones) - the unit armorer would destroy them by crushing them - they were cheap as chips to make and it gave Commonwealth units lots of Automatic weapons (up from 3 Thompsons per battalion in May 1940) very quickly.
One of the problems with Sten guns was that the British went from virtually no SMGs with little 'tribal' experience of using them to having fucking millions of the bastard things in a very short period of time - boys will be boys and accidents will happen - and of course every squaddie knew someone who had seen some one drop one and it dump the mag! The British were also used to making quality kit and of course would make obvious comparisons between the Thompson with its superb finish and the 'utilitarian' Sten - forgetting that you could arm 20 guys with Sten guns for the cost of 1 Thompson.
The jamming was a legacy of the single feed Magazine which was a direct copy of the German magazine for the MP38/40 - the Sterling magazine was by comparison one of the best ever made.
The enemy of perfection is the good enough and the Sten was good enough