[fenomas]

> Am I wrong in feeling that callback hell is a symptom of bad design?

I think so, yes. Chaining together four consecutive web service requests might be a bad smell, but there are lots of other reasons to use async calls - waiting on a timeout, a worker, using IndexedDB, waiting on a user event or an animation, etc, etc.

In general if something can be done asynchronously it probably should be, so depending on the domain I'd say a lack of callbacks can be suspicious.