Sometimes the Government seeks the best overall value, and at times simply lowest cost. But even when low price is determinative, the bidder must still meet minimum technical qualifications. In a recent case, Level 3 Communications lost a major contract with the Dept. of Defense to Verizon, whose bid exceeded theirs by nearly $40 million. Level 3 was disqualified for what it thought were trivial reasons. When Level 3 protested, it got no relief from GAO, but the Court of Federal Claims came to their rescue.
More at Petrillo & Powell's Patterns of Procurement.