Ushahidi's Patrick Meier has a fantastic graph of deployment time for Ushahidi's amazing crisis-mapping solution (which has been deployed for such diverse projects as Haiti post-earthquake, the Gulf Coast post-BP, and DC's 2009/10 "Snowmageddon"):
The simplicity of Ushahidi setup sometimes leads to some crestfallen administrators.
Just because you bought a domain name and ran the Ushahidi installer doesn’t mean that anyone is going to use they system — and even if you somehow get a lot of reports, you might not be relevant to the existing systems [...] Ushahidi is only 10% of solution.”
I'd posit that this 10%/90% division applies to any and all "tech" solutions to real-world problems.
The technology is increasingly (perhaps it always has been) the easy part. It's a shiny, tangible product with clear "milestones" of in development, in testing, deployed, working. Lots of happy checkboxes for any M&E report, and photo-ops to generate great press and build excitement and community around a technology.
The secret sauce, though, is the massive, intangible, full-of-hard-work-and-sweat 90% of any approach. It's making sure the technology is a natural fit, working with partners on the ground, translating, training, supporting, outreach, and tweaking that goes on to customized and localize the technology to being relevant to the problem at hand. It's thinking from the perspective of the nail and seeing everything start looking like hammers, not vice-versa.
Unfortunately, not enough people keep this in mind and even fewer make it clear and explicit like Patrick has.