Perhaps many of the missing functions are due to lack of funds.
Discussion
By "functions", do you mean software features or human business roles?
should be the lack of personnel function.
Most non-dev software roles scale really well, like marketing, sales, dev-ops, test, customer support, analysis, etc.
That's why I keep encouraging the devs to form project teams, join project teams, or combine/integrate project teams, so that they can "afford" to set aside or recruit some resources for these other roles. Or latch onto a group that already has them all (like ours), and make yourself useful.