News Courtesy of SearchEngineLand.com:
With Google manual actions, real people at Google apply penalties to websites that are not complying with Google’s Webmaster guidelines. Google launched a manual actions viewer in Google Search Console in 2013 to communicate human-added penalties to your website.
John Mueller, a Google webmaster trends analysts, said Friday on Twitter that sometimes manual actions can be replaced by an algorithmic penalty. We have known for many years that manual actions can expire. Often after a manual action expires, Google will reissue it if the violation hasn’t been addressed. But sometimes, John said, a manual action will expire and won’t renew because an algorithm has taken over.
Ryan’s Take 
I’ve been fortunate to never have received a manual action penalty for any of my websites. Because of this, it makes me believe that you have to be extremely negligent or deceptive to get one. Although, it’s nice to have Google Search Console report such actions to make them easier to diagnose and resolve just in case.
I truly believe that Google is in the process of shying away from penalties in favor of devaluing certain factors. For instance, let’s say a website has a bunch of spammy links pointing to it. In previous years having bad quality backlinks could actually hurt your website in the SERPs significantly. While there still might be a penalty, it doesn’t make sense punish websites. Why? Negative SEO.
Negative SEO is when someone (usually a competitor) tries to inflict damage on your website by intentionally doing things that break Google’s webmaster guidelines. It’s been a problem for years but has become more apparent with competition rising for high volume keywords. I think it is a scumbag move and akin to cheating. There is nothing wrong with competition, however, improve your own website presence instead of trying to hurt a rival.
Obviously, Google is aware of negative SEO. The best way for them to combat it is to limit or remove penalties altogether. Does it really matter if a website has thousands of crummy backlinks? Chances are no one is clicking on them anyway. It’s better to ignore them. Being the multi-billion dollar company that they are, it’s not too far of a stretch to think that they are able to establish patterns over time. Any anomalies, such as a bunch of bad backlinks suddenly appearing, should be a clue that it isn’t sanctioned by the webmaster.
