Something I have witnessed a lot of and to be honest, I have done for a few years now is account managers / project managers / tea ladies discussing briefs with designers talking about how it should look and how things function often resulting with the designer just nodding his head saying, “yeah we can do that easy.”
More often than not, when the developers get the first sniff of the job, the functionality that was discussed will either take a lot longer than the 5 minutes quoted by the project manager, there isn’t enough detail to build or isn’t possible in its current format.
Either way, the account manager isn’t thinking, “Why didnt I ask first?” By this point, he’s handed you the bomb and is walking off, job done.
Something I worked hard to get put into place in the team I managed a couple of years back was for a dev and designer to be present when briefs were being discussed. This helped the process and ensured whoever was going to sell it / write it up knew the score and that there would be no nasty surprises when they hit send on the email.
So if you are an account handler or project manager, just because you can log into your Yahoo email and have a tumblr account doesn’t mean you know how things work.
Use your devs.