It's such a broad cop out. Very much like the "we use (horribly intrusive surveillance technology that is complete overkill for any imaginable purpose today, is almost certainly illegal to collect without explicit consent, but we may find useful in 5 years when we trawl all the logs and mine it for a tiny modicum of profitable edge) to improve our products and services, and some other random long sentences that sound innocuous and something else, look at the fluffy bunny, (huge) *CONTINUE* button, pre-selected (tiny) not right now, doesn't even look like a button".

Improving the ad experience could mean they stick a probe up your rectum and see if your bowels move better or not, for all they care.