[drothlis]

They probably mean incremental builds, where the actual compilation doesn't overshadow the "coordination" work.

In my (artificial) benchmark, make scaled poorly, taking 70 seconds to process 100k C files worth of dependencies, vs. ninja's 1.5 seconds: https://david.rothlis.net/ninja-benchmark/

Most of make's time was spent processing the ".d" files containing header dependencies (Ninja has a special optimisation for these files, where it reads them the first time they're created, inserts the dependency information into a binary database, then deletes them so it doesn't have to parse them in future invocations).

In real world projects, you often end up "abusing" make to add behaviour such as detecting if the compilation flags have changed, and this can make your makefiles slower; whereas ninja has those features built in. Apparently this made a big difference in build times for Chromium (where ninja was born). See this comment by the ninja's author: https://news.ycombinator.com/item?id=23182469