When advertising is at its best we, as the audience, get wonderfully lost in its content. We're not questioning why things are happening in an ad. We're not getting hung up on copy points. We're not asking why a regular guy is playing one-on-one with an NBA player. Rather, we are just enjoying the moment.
Like watching "Forrest Gump." We never say there's no way this could ever happen, we just root for Forrest. This is the sign of good storytelling and good production. Really good advertising wants to attract attention and present an idea but it doesn't want the audience to think too much about the ad. When the details get in the way, the ad doesn't work as well.
There's research to back this up. Robert Heath at the University of Bath has proven the effectiveness of low level processing on recall, especially when advertising carries high emotion. And a 1989 study by Robert Bornstein confirmed that the less aware we are of the elements in advertising the better the ads are likely to work because the viewer has less opportunity to rationally evaluate and contradict things. So we sit back, enjoy and connect.