Proper usage of 'more often' , 'more frequent'.?

When we read an article on the internet saying that some Event X takes place more often than you think. What is in the mind of the author who writes this article? Does the usage of more often implies that

1.)the author thinks that readers of his article already think that the event takes place at a lower frequency level

OR

2.)the author thinks that his audience might think that event never takes place ,

OR

3.) both scenarios 1and 2 are possible?

Also can anyone tell what exactly the usage of more common and more often implies in day to day English conversations??