You can find yourself sometimes with a client or a colleague who has an insurmountable problem and 'insurmountable' can be good; often it means that they have not yet finished evaluating their choices and martialling their resources.
But sometimes, they just have the inertia of not wanting to start because they don't want to fail.
Perhaps remind them, in the week of the release of the film, Lincoln, of Abraham's road to the White House. If they really have a goal that they believe they can achieve, it isn't a question of 'if' but only 'when'.
Lincoln's road to the White House - had this on my pc for ever
Failed in business in 1831
Defeated for Legislature in 1832
Second failure in business in 1833
Defeated for Speaker in 1838
Defeated for Elector in 1840
Defeated for Congress in 1843
Defeated for Congress in 1848
Defeated for Senate in 1855
Defeated for Vice President in 1856
Defeated for Senate in 1858
Elected President in 1860
It brings home that there are no unresourceful people - only unresourceful states.