Likes created by fake accounts or people without real intent are bad for people on Facebook, advertisers and Facebook itself.
Facebook has a strong incentive to aggressively go after the bad actors behind fake likes, because businesses and people who use Facebook platform want real connections and results. Businesses won't achieve results and could end up doing less business on Facebook if the people they're connected to aren't real.
It's in Facebook best interest to make sure that interactions are authentic, so Facebook has a number of teams that detect fraudulent activity and shut it down.
What are fake likes?What are fake likes?
How and why inauthentic likes are generated
There are four primary ways in which fake likes are generated:
4- Compromised accounts that have been infected with malware, causing the accounts to like Pages without the knowledge of the account owners