imap vs pop3

It has nothing to do with being more stable; the difference between the two is: POP is a localized account > that means your emails are on your ISP's server and downloaded to your Mac. They will then stay on your Mac and will not be automatically visible on another device (such as an iPhone if you have one for instance). The IMAP is more of an online account > the emails are your ISP's server and stay there visible on all devices you have set up accounts on. Additionally, they are downloaded to your machine, but unless you move them from the Inbox to a folder you created, they will not be there when you go offline/no longer connected to the internet.

If you have just one device and don't need to see them on others and want to work on them while offline, then POP3 is fine.

Having said that, most mail apps/computers are automatically establishing IMAP accounts nowadays. If you want to have a POP3, you'd need to set that up manually.

Actually, I have one myself because I do not need to access it from any other device. I have to admit I do not know if it may no longer be supported at some point - it does not seem to be the ISP although some only offer IMAP what with all the smart phones and mobile devices out there, but the Apple Mail app is doing the automatic IMAP setup when you want to set up a Mail account. But, as I said, you can manually configure it to POP3. My personal opinion: Apple has decided that everyone wants IMAP, so that is the automatic setup.