Here’s a trick I have found to avoid annoying telemarketer calls. I have been employing it with some success for a few years now.

The trick is quite simple: never say “hello” twice. If you say “hello” and get no response, resist the temptation to say “hello” again. Just hang up.

In my experience, 90% of the time when I have to say “hello” twice, it turns out to be a telemarketer. If it was actually a real call, they’ll call back. No worries.

The reason this works is that many telemarketing call centres use machines called “predictive auto-diallers”. These machines attempt to predict when an operator will become free to handle another call, based on how long the operators usually take, and how long people usually take to answer the phone. Sometimes the prediction is wrong, and you answer the phone before an operator is available to talk to you. That’s when you find yourself saying “hello” twice.

Don’t do it. Just hang up.