I don't control the situation I've walked into and the events preceding, but I can control the outcomes. I'm not there to take credit for other people's work, but if management isn't on board with their ideas, I can oftentimes help to frame the message so it will be better received. If the "rank and file" is willing to work with me, I'm going to bend over backwards to make sure they have a seat at the table and that their existing work is recognized. I get paid either way so there's no point in trying to take all the credit.
I understand that, as the employee whose ideas have gone unheard, this whole situation may be perceived as a ridiculous waste of time and money. Sometimes it actually is. It might be management's own inability to discern good ideas from bad, a poor understanding of the business or technology problems they face, the solutions available on the market, or lack of trust in their own staff.
More often it's simply managers looking for a broader perspective from an outsider who has engaged other organizations with similar business and technology problems. I start with the understanding that they're sincerely looking to do the right thing until they give me reason to believe otherwise.