Lower them expectations! Make it seem hopeless/doomed/DOA. Then dazzle.
Ladies & gentlemen: think about your comments here. No professional developer is going to spend valuable time & money developing for a product that may or may not later have someone to buy whatever they develop. To make that concept work, you probably need Apple giving these away to developers WITH subsidizing cash to motivate development until a market can provide the motivation (revenue). Else, this would be aiming for the home-brew/hobbiest crowd at best (those with no monetary objective but some programming skills).
This is the same nonsense thinking that basically goes with: since Mx and Metal are far beyond great/best, game developers should be making all of the AAA games for Mac... as if it is the technology ALONE that motivates where developers allocate resources. It's not. Money motivates all business efforts. Few to none will want to potentially waste lots of time, money & resources on something that only MIGHT yield a ROI down the road somewhere, when they can instead put those same variables towards opportunities with known and tangible upside.
Whether Goggles, Car, Watch, Tablet, Phone, Pod or Mac, the Maker of such products needs big adoption to motivate those who can expand the experiences with such products develop for them. OR Maker needs to basically "bribe" developers to develop for them so that the very same PRIME motivational force is in play whether there is an eventual market to buy whatever is developed or not.
Logically, this speculation that developers will buy these and then invest sizable amounts of their own money developing fantastic things for them only on hope that at some point in the future, lots of consumers will buy these too so that all that time, money & effort can finally be monetized makes no sense or $en$e at all.
I suspect this is simple marketing strategy to cut expectations ahead of a big reveal... like "iPad will cost $1000."