Many webmasters have decided to not include any external links on their website because there is a fear that their website will get a penalty if the link they linked to will hurt them for some reason. Gary Illyes of Google has come out and said that he hates websites do not link out to other websites while John Mueller of Google has come out and said Google does not penalize sites that do not link out to other sites.
So here comes the big question, does Google penalize sites that do not have any external links?
The answer is NO, Google does NOT penalize sites that do not have any external links. John Mueller has reiterated and said: “It’s really solely up to the site what they want to publish & how they want to link. If their site serves their audience well, that’s fine. If you think you can run a site that serves the audience even better, then go for it & make that site yourself!”
So, there it is, in terms of links, it is optional for webmasters to put external links on their websites as Google does not penalize sites that do not have any external links.