54% of users cite ad clutter as the biggest obstacle to good user experience

The Interactive Advertising Bureau brings some user experience homepage statistics from a different angle; via insight from those within the digital marketing industry. Apart from overcoming the challenge of displaying ads without putting off website visitors, issues UX designers have the most difficulty with include creative quality – 37% and overall experience – 36%.

Source:
https://www.clickz.com/stats-of-the-week-ux-gets-an-f/101769/