I've heard of large consulting companies that do a "bait and switch" where the client initially talks to a fantastic technical person prior to signing a contract, then never hears from them again.
Similar to large law firms; a senior partner closes the deal, and then they shuffle you off onto an associate fresh off the bar (who often still bills out at the full senior partner rate!)
Sometimes law firms don't even really disclose who's doing the work, and sometimes in their invoices they'll have a paralegal's initials under the "Atty" column.
This is sometimes true even for very large and reputable law firms.
Every solution architect/ pre sales engineer you talk to before the ink is signed isn't there to do the work, they're there to build trust and confidence that the other folks who can't talk to a client are just as talented.
Also you definitely hear from us again as we bill 4 hours a week or what have you for "Quality Assurance."
There are some legal sensitivities here: the company is hiring a vendor to provide a service, and risks co-employment issues if they start managing the vendor's staff in any way, including interviewing them.
This is standard operating procedure with large Indian outsourcing-companies.
Get the contract using great people. Before the ink on the contract is dry, send in hopelessly underqualified staff. By the time the client finds out, their "old" internal resources are long gone, bonuses have been paid out to management for reducing cost etc.
i work for a consulting company and prefer to cradle-to-grave my projects but it makes it hard to move up the corporate ladder. I'm working on a proposal now for a large project that will span at least 3 years. If I ask to get staffed on it then i know it will get delivered as sold and I may get promoted at the end but definitely won't get promoted during the project. On the other hand, if i'm an author on three or four wins for large projects over a year then i'm much more likely to get promoted regardless of how those turnout at the end of their schedules.