In US Intel parlance: "Low confidence means it’s too fragmented, it isn’t authenticated & major concerns about the credibility of the sources!"

"...In U.S. intelligence analytical parlance, “moderate confidence” generally means that information lacks sufficient corroboration, while low confidence usually means that it’s too fragmented, it isn’t authenticated and there are major concerns about the credibility of the sources.The president’s restraint also stemmed from lingering popular anger over his predecessor’s use of bogus and exaggerated intelligence to fan support for the 2003 U.S.-led invasion of Iraq, and his own reluctance to become embroiled in another foreign war as he pulls U.S. combat forces out of Afghanistan after nearly 12 years of conflict..., ..., ...,
Rep. Brad Sherman, D-Calif., a member of the House Foreign Affairs Committee, urged the United States to move slowly and to work with its allies and with Russia – which, along with Iran, is Assad’s main foreign supporter – to forge a response.
“The downside to Syria is there are elements of the opposition that are just as bad as the elements that control the government,” he said, referring to al Qaida-allied Islamist rebels. “It’s not just who you’re against, it’s who you’re for.”...
 skepticism grew among some experts, who questioned why Assad would use sarin only on a small scale and wondered why there weren’t more casualties if chemical weapons had been used as extensively as opposition activists have asserted.
“If you drop a bomb with sarin, how do you nail only one person?” asked Jeffrey Lewis, an expert with the Monterey Institute of International Studies...."