It used to be so crappy back in the Windows 7 days, but in the recent years with it being built into Windows, Microsoft has put in a lot of work into getting it at an acceptable level, and even some third party anti virus comparison tests show it being above 95% effective and head to head with some of the other third party AVs out there. I have used Windows Defender and it's served me well for the past few years.

Most are bundled with so much crap, they bog down your system basically, or include things that are borderline malware themselves. Most of the AVs out there have gone downhill in the past 10 years. I personally can't recommend any third party AVs, paid, and especially free. There's other things, but at the end of the day if you do simple things like these, your AV will gather dust, since you'll avoid the majority of the common malware people get. Old software and outdated operating systems are prime targets for getting malware and hacked. Also make sure all of your software and Windows is up to date as soon as possible. Avoid scam emails and flag and delete any that seem fishy. Definitely avoid downloading attachments from emails if you can help it.

Many bundle extra crap, when say you want to download a web browser only. Avoid third party websites to download software. That means avoid pirating games and software, those are huge risks. You should learn what bad websites are, and to avoid them. You can whitelist sites you support, but I would let it block everything.

You need to do things like run a good adblocker, and load up on anti malware lists. What I am getting at is you need to reduce your chances of getting infected, so you can be more at ease. You can't expect the AV to do everything. You can rely on an antivirus and anti malware program to do the work for you, but you should be the first line of defense.

Antimalware reddit