Even that seems excessive to me on a personal line. My voicemail exists. It's up to the caller if they wish to use it. If so, I will use the message they left to decide if I wish to speak to them. If they don't use it or the message doesn't sound like something with which I would like to engage, we will not speak.

Of course, this process changes if I'm doing something like looking for a job, in which case I might answer unknown numbers but only with "hello?" How the rest of the conversation goes depends on how they open. I've received calls from less reputable recruiters (and creditors) where the call started with "beep Please hold for the next available representative." The answer to that is no. If you called me, unless I expected it and needed something from you, I'm not holding for you. However, if the call starts with something like "hello, is this [my name]?" then we might talk.

In most cases, unknown numbers calling me want something from me. In many of those cases, I don't want to give them whatever it is. I don't owe them anything, so it's up to them to convince me it's worth talking.

However, if you are inclined to answer unknown calls, I agree that "'lo?" is far better than "hello, this is [your full name]."