It is very easy to believe that simple apps are simple. They aren't.
Typically the platform underneath is MASSIVELY complicated and richly functional. And if it is not capable of superhuman feats, your apps will really suck. The dividing line between what is app and what is platform is very gray.
I'm not always sure that the people who make decisions about this stuff at software companies truly get this concept.
A corollary to this -- your customers don't care what is app and what is platform. They just want a solution to their problem. I see a lot of companies touting their platform as the primary differentiator and I think this is a mistake. *Maybe* ok for mature companies in a given space that can legitimately claim platform leadership. Like SAP for Netweaver for example. Or if this is your primary offering in the space, e.g. Amazon and EC2. But if you business is apps, I think a solution approach is vastly better.
The thing is this. In enterprise, you don't find many (any?) business buyers who love talking about platforms. This holds up pretty much regardless of where in the enterprise you vector into.
IT doesn't love platforms because platforms sound ... BIG. Expensive. Disruptive to adopt. Sticky and "locked in." Remember the way old days when we had Windows anti-trust proceedings? Everyone has forgotten the dark days of platforms. But history doesn't matter. IT has a visceral reaction because platforms smell like HEAVY LIFTING.
Business buyers (i.e. VP Sales) doesn't love a platform story because largely they don't understand a platform story. The reaction is more "huh?" than anything else. They want an app. They want magic. Apps are where the magic is. Talk platform here and you won't get a second meeting.
In the end platform is something you build towards for your company. Apps are for your customers, platform is for you. It's like the old sailing adage... one hand for you, one hand for the boat. It is an "inside the company" religion, and a good one at that. Preserve and invest in the platform and it will pay dividends. It lowers your cost to develop and speeds your time to market. All great things. But from a customer perspective ... meh.
A postscript. Analysts love to talk about platforms.
Update: Dec 2012. After very careful consideration, I think that CMOs do actually like platforms. It's a whole different thing selling to the CMO.