[A Navy Vet]

"The trick is to make your message so unimportant that no one wants to know what you’re saying. There is no technology known that can capture every phone message to every number."

Unless you become a suspect for even some reason, no matter how innocent. Then the technology kicks in.

[count-your-change]

If someone is really, really interested in what you communicate by any means whatsoever they can discover it. It only a matter of effort expended.
You can frustrate their efforts if you know about them but your actions show you know you’re being monitored and the methods are adjusted.

And if that doesn’t work Vito will come and beat on the soles of your feet with a pipe until you talk.