Earlier quoted context omitted.
You can install it, use it, benchmark it, and check everything yourself. It's not open-source, but there is plenty of closed-source proprietary software, and plenty of buyers who care about solving their problems and paying money to get that done (and ensure the vendor stays alive). If you don't want to use a closed-source product then that's your prerogative, but I don't see how you're making a dev/engineering decis…
because the source is important, it tells the buyer they have a future if they no longer like your services; closed source means they are locked into whatever fresh hell might come upon your company which in turn unleashes fresh hell upon their decision to buy in.. in 2018+ it's just a smart decision to make
A real technical reason might be "the ability to fix the software ourselves" or "easier debugging of the software". Avoiding vendor lock-in isn't a technical decision