I really don’t think there is one better than the other, I simply think they are different solution to the same problem and depends on the need of each problem to define which one to use. As a matter of fact, I would not recomend Jekyll to anyone, Jekyll normally require some technical knowledge to use it and lacks from a graphic interface. Because of this, if the site’s content is going to be managed by non technical users is probably not the option to use.
Being said that, possible the top advantage is that as generates static content it requires less resources during site execution and could even work completly on a CDN or cheap or free hosting options, which suppose a great advantage on performance and operative cost.
For any additional feature that the site requires that needs more dinamicity you could combine Jekyll with options like Node.js or any application in any other language or platform.
Besides these, Jekyll is build on Ruby and can easily be extended through plugins.
Personally, the decision to migrate my blog to Jekyll is based on 3 reasons: - Performance of my blog: I want my blog to be as fast as possible and nothing beats static files. - Experimentation and learning: My blog is and always has being a sandbox where I experiment in the real world with technologies that I want to learn. - Low maintenance: Once Jekyll is configured, the maintenance is literally minimum and I can focus on writing more often.
The complete code of my blog can be found in GitHub.