1. Eliminating runtime errors(type mismatches, segmentation faults, and null pointer exceptions are a few problems that have been hammered on a lot and in some languages eliminated entirely). 2. Being able to manage a large project effectively. Things like build systems, code editors, debuggers, and perhaps most of all, access to libraries/hardware for the problem domain.

Newer general-purpose languages(under ~5-10 years) tend to offer compelling features in the first case, but almost nothing in the second, which makes a commercial project in them an expensive prospect.