WTF? Without context "so-so" is indecipherable. As a native English speaker it was not clear what the original meaning was. My partner, native German speaker and fluent in English, was equally flummoxed by this. Only after seeing the answer was the question clear. If two university educated folks with fluency in both the source and target language find this question unworkable, perhaps it should be fixed. Just saying...
It can mean either, in different contexts.
As a response to Wie geht's? "How are you?", Es geht. means "So-so".
When you're talking about, say, a machine you just built, then if someone asks, Und? Geht's? and you respond Ja, es geht!, then that means "And? Does it work? -- Yes, it works!"
According to the dictionary, gehen or geht means to go or walking not work or working.
Kinda confusing, but makes more sense when asked with "How goes it?" which in turn makes the question "Wie gehts?" make more sense too.
Wie gehts? - How are you (going)? (How does it go/How goes it)
Es gehts = It goes (a rather neutral and flat response similar to ... so so!)
this is so weird.... even when i check the answer <<< but when i read the discussion i got the meaning it's just the same in russian language when you ask some one about something and it's not perfectly good, they say "so,so" in arabic which is my mother tongue it's the same meaning of "MASHY EL HAAL" > (ماشى الحال )
which means it's not that fine but it works as it is > it's really funny how all cultures have the same answer for something we are not satisfied with, but it shall work !!!! :D