The used car salesman: Dell
Dell has a good mobile site: functional, generally well prioritized, and graphically elegant compared to the austerity of many mobile sites. The problem is that you can't cross the car lot to check out this fine piece of machinery without being intercepted by the car salesman. I refer to the pernicious habit (Dell is just one prominent offender) of placing an intercept screen in front of the mobile site, demanding that the user accept or decline the generous offer to download the brand's mobile app.

Others have made this point better than I, but let me make it plain: mobile app and mobile site use cases are different. The user standing in the store aisle avidly seeking more specs on a Dell laptop doesn't want the app; they want the info as quickly as they can get it. White Horse's own study on in-aisle mobile found that users were more than twice as likely to use the mobile web, and most users in our study carried only one or two retailer or manufacturer mobile apps on their phone. That jives with a study by Deloitte that found that 80 percent of branded apps were downloaded fewer than 1,000 times.
It's perfectly legitimate for Dell to tout its mobile app through a link on its mobile site, as many brands do. The app will find favor with the small minority of visitors that regularly make Dell purchases, or follow the brand closely. All other visitors will be annoyed by the car salesman, and some will walk off the lot.