I once nearly had a scammer in tears, by the sound of her, after I said that she should be ashamed of herself for trying to steal hardworking people's money and asked, does your mother know what you do for a living, I bet she would be ashamed of you if she did and suggested she got an honest job. Her supervisor joined into the call at that moment and tried to convince me that the call was genuine, while she composed herself, then she tried to continue.
A call I had last week was much more convincing, a guy with an english accent on an initially clear line, claiming to be a BT engineer, informing me my line was going to be cut off for 4 days engineering work at the exchange. Although I thought it was probably a fraud, because he said BT, rather than Openreach, I have had calls from BT engineers in the past working on the phoneline, and I know they are working on closing down the exchange and moving all lines to voip at the street cabinets, so I didn't hang up. He then said to check my email for a pin code that I would need to enter to connect via an alternative connection they were going to provide. They'd done what I correctly guessed was a forgotten password change request on BT's website to send out an email to try to make them look authentic, which had gone to my late father's email. Rather an oversight by BT is the email just gives the 4 character code and doesn't have the typical warning, that you might expect to tell you someone requested a change of password and to ignore it if it wasn't you. Then after a bit more faffing around he asked me to do a search in google and started spelling out a..n..y.. Which I guessed he was going to ask me to install Anydesk and told him to get lost.