Not surprising, and largely driven by American failures:

• Failure to devote sufficient resources.
• Failure to deal with Pakistani government support (by which I mean their intelligence service, the ISI) of the Taliban.
• Just plain stupidity:

Although it is a volatile area and a centre of Taliban support, the Dutch forces had forged close links with community leaders, cutting down the fighting, until a botched poppy eradication program by a US private security firm a few months ago, analysts say.

“Uruzgan was going OK until they went in with tractors and started ripping the poppy fields up,” said the Kabul-based security analyst. “The Dutch had a good relationship with the people down there, the local leaders, but when they rip up your crop, what do you do? You grab your gun. They didn’t even do that much damage to the crops in the end.”

To quote John Wilkes Booth, “Useless”.