Lots of things we do for improved security, both physically and electronically, reduces practicality, which is why houses with alarms get robbed due to the person not actually arming the alarm. You have a company, you have data that needs to be as secure as possible, you make sure they all have the same phone with the tech, tech once in place, easy to use at least.
How about those people who don't lock their safe door because it's too impractical to open it using combination. I know such a guy.
Your teams life depends on secure com, less practical to make sure you're all communicating using same secure tech, but the pay off is obviously there in terms of loss of practicality.
So, basic formula of cost, how practical it is to use/ to what you may lose by not having it.
Friend of mine owns 100 mil + per year company, and I told him he was f-ing nuts talking about sensitive topics over his cell phone with his lawyers (and he's often in court fighting with the gubment) and business related topics (of which a single intercepted email or phone call could cost him everything) was a very bad idea.
The fix was having the essential people he talks with add the tech to their phones (which he purchased for them) he's GTG.
Just adding two cents to your comments, not disagreeing with what you post per se.
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