It can be very hard to hire good embedded developers (I know, we are trying). Also, until you reach a certain scale, the work load tends to be highly variable. What these places need to do is hire one of the many good design houses that can quickly knock out a production-worthy design from an Arduino prototype and put you in contact with reliable contract manufactures to crank out volume.
My employer has an EE/embedded team of 3, and we still rely on a local design house to rev our PCB's, do the generic infrastructure components of the embedded s/w, and design test fixtures. We write specs for electronics and keep the "secret sauce" firmware in house. There are other benefits -- as I write this we have an expensive instrument that we could never justify purchasing sitting on our lab bench because we borrowed it from our design house. We can get a few hours of specialist time here and there for things like FCC compliance testing to augment our in-house expertise.
One person who has been around the track enough laps to be able to write good specs and do program management is sufficient in the early days.
My employer has an EE/embedded team of 3, and we still rely on a local design house to rev our PCB's, do the generic infrastructure components of the embedded s/w, and design test fixtures. We write specs for electronics and keep the "secret sauce" firmware in house. There are other benefits -- as I write this we have an expensive instrument that we could never justify purchasing sitting on our lab bench because we borrowed it from our design house. We can get a few hours of specialist time here and there for things like FCC compliance testing to augment our in-house expertise.
One person who has been around the track enough laps to be able to write good specs and do program management is sufficient in the early days.