Very few people actually like adverts, but even fewer people like the ones that get all up in your face when you're trying to read something. Thankfully Google has announced that it's cracking down on mobile sites that serve up obstructive advertisements.
In a blog post yesterday, Google Project Manager Doantam Phan said:
"Pages that show intrusive interstitials provide a poorer experience to users than other pages where content is immediately accessible. This can be problematic on mobile devices where screens are often smaller. To improve the mobile search experience, after January 10, 2017, pages where content is not easily accessible to a user on the transition from the mobile search results may not rank as highly."
So what does Google define as 'obtrusive'? Any adverts that covert the content on page, or require you to close them before you can do what you need to do. Any sites that don't play ball will end up taking a hit on their SEO rankings.
The post also revealed that Google would be removing the Mobile Friendly label on search results, due to the fact that the majority of results meet that criteria. [Google]