We all feel like management contributes nothing, right? But they seem to always be around successful companies. I dunno, correlation isn’t causation, but I think there must be something there.
Weirdly enough, many unsuccessful companies I know of had management too. Correlation isn't causation, but maybe there's something there.
There are also plenty of successful companies and projects without management too. Basically every 1-to-5ish-man consulting shop has zero managers and some of those do wildly well. Some of the best indie games, produced by teams of 3 or 4, had zero dedicated management. Most open source projects have effectively 0 management.
Valve, famously, kept a flat organizational structure for a long time, and certainly was somewhat successful.