Everybody (or nearly everybody) knows Raspberry PI. A lot of people also know Compute module (version CM3). It looks nice, has a lot of processing power, good price, …. so we started the project with this module.
Raspberry CM3 module fits nicely into the selected box (DIN Rail enclosure).
However during the development it turned out electrical connection is really complicated because the CM3 module lacks connections that are standard for industrial use. The module only has a USB port and 2 UARTs. Also this solution required quite a large amount of external components that made the design of base PCB rather complicated. Because of these shortcomings only the functional prototypes were created, development was paused and no production stage devices exist as of now.
Since most use cases do not require the Linux module to be so powerful and focus more on cost-effectivity, subsequent designs are based on different platforms. In case a need for a powerful device based on a platform with strong software and community support arises the designs can be easily adapted to use the latest CM3+ modules and completed.