When the GAO agrees there were problems in how a contract was advertised or awarded, it typically will direct the federal agency to reconsider its decision, but that process doesn't usually favor the protestor, according to Alan Chvotkin, senior vice president of the Professional Services Council in Arlington, Va.
"Many of the protesters take note of the fact that after winning the protest, they still don't win the business," said Mr. Chvotkin.
In contract protests, the GAO gives the government a "high degree of deference," said Steven Schooner, co-director of George Washington University's government procurement law program.
To do otherwise would invite what Mr. Schooner called a "cycle of protests" that could hamper the government's ability to operate.
When a protest is filed, an agency might have to delay work on a contract until the matter is settled.
The number of protests made each year represents just a fraction of the tens of thousands of transactions the government has with the private sector, he said.
But many contractors won't protest because they'll be viewed as troublemakers and be cut out of future awards, critics said. Or, their silence might be rewarded in another way.
"If you don't win, you may get a piece of the contract as a subcontractor," said Keith Ashdown, chief investigator at Taxpayers for Common Sense in Washington. "But if you rock the boat, you won't get anything."
The appeal of filing a protest with the GAO is that it is free and fast. While the office lacks the clout of the judicial branch, it's required to resolve cases within 100 days, and legal fees are usually less.