macOS has its own built-in protection mechanism that does that job for you already – although without a user interface. It also updates itself automatically once a new treat is discovered.
What other apps that call themselves virus scanners may offer you as an extra is discovery and removal of adwares that are installed by you(!) or any other user with admin privileges – and act mostly as an extension of Safari, Chrome, Firefox.
So macOS will not detect adware ‘infections’ because these actually do no harm to your files – they are not virus, but they simple redirect advertisement delivery.
Infections I have to deal with on Macs turn out to be 99.998% adwares in each case, with 0.001% spyware and 0.001% intentional intrusion.
Antivirus apps can also offer you the feeling of ’being scared and protected at the same time’ promising if a new ransomware is discovered, then THEY will be the ‘one’ and ‘first’ to offer you the BEST protection, because their security specialist are working 24/7/365 a year detecting new threats and they do it even while sleeping…
…the actual difference is that Antivirus developers do the job with lot’s of buzz – like Malwarebytes – and Apples own team dedicated to this task works in silence.
But you have to make a buzz if you want to sell your product that’s true. You have to make the people feel ‘aware of the dangers of the internet’ …or in plain words: make them scared – it’s a common psychological method in advertisement business.
Making you feeling afraid is a good business, makes a yearly income of $25-60 per license sold / computer / year to antivirus developers.
What everyone could do instead is not to install any application from other sources than AppStore or straight from the developers, AND not using Adobe Flash Plugin and Java at all cause, also avoiding unnecessary browser extensions.
My experience is that if there’s an effective ad blocker – like AdGuard for example -. then it’s 99% true that Mac owners with admin rights will not infect their computers unintentionally – for the simple reason of malware being spread by web advertisement primarily – and these will be blocked.
One more experience I would like to share in order to clean the myth about antivirus apps that promise the false hope of staying clean or protecting us:
there was a malware infection spreading last year – WeKnow.ac – and one of my clients managed to install it via a webpage that made her believe by an advertisement that the Flash plugin needed an update in order to show the content of the webpage she was visiting.
For example Malwarebytes that spends an enormous amount of money making Mac users believe their product is will deliver you protection and it’s ‘essential to have’ did not even detect the infection, although I have to admit there was already a fresh forum dedicated to it on their support site – without an actual cure that would work for everyone (just tips), so they knew about it’s existence at least.
I have managed to remove the components of this infection except one ‘thing’ the have remained as ‘cosmetic’ – and a workaround was enough and faster, than to reinstall the whole computer – that the client had no time and money for – just for the record what this ‘cosmetic’ thing was: the ‘homepage’ of Safari in Preferences could not be changed.
A few months later this client of mine called me about another issue (like a printer problem…) and out of curiosity I have checked the computer with the above-mentioned antivirus app again (freshly installed) – what do you think, did it detect that last trace of infection I was not able to remove? Nope, it did not.
Having an antivirus on a mac builds false hopes, and is a waste of money and energy that every user should had used for integrating safety protocols instead but most importantly to ’think’ before installing anything.
My lifetime experience is that antivirus apps will NOT protect your Mac when real shit happens, however the opposite might be true for Windows that is a real piece of security nightmare by its core architecture.
When your mac get’s infected, you will need IT support and no antivirus app will protect you, because of the speed malware are spreading these years.
When a new malware appears on the internet, no third-party antivirus developers will be faster to deliver cure against it – and you can be sure Apples employees will not wait and drink cocktails instead of acting fast as possible.
If you are responsible for the IT infrastructure of a medium to big size company however, although based on experience it makes no sense to install any antivirus on Macs within that environment, you will actually do so because of a simple, understandable reason: you have to make ‘more’ than it’s necessary – even if that means money being wasted.