May it be something we learned at school from performing well on tests by having the answers. Or may it be from our desire to remove uncertainty. People will often focus on providing the one and only solution.
It is addressing the world from a restricted view of the way life unfolds for us. As toddlers humans experience many problems to which there was one solution. For most toddlers, the system is easy. For example, when they are hungry they start crying until they receive food. Along the way, they learn to recognize the patterns leading to successfully receiving food and adapting to them. It becomes their solution to the problem of feeling hungry.
Most situations encountered as adults are more complex than that. They go beyond simple cause-and-effect algorithms. Symptoms may appear as problems. There might be a given solution for a problem, but then it often is a solution that opens the door to other problems. Or the problem that is being solved is part of the cycle of life and reappears regularly in a slightly different fashion.
In all of these, there could be an easy solution. It either requires shifting the perception of the expected solution. That is, the ability to see the problem from a perspective that accepts that the problem may not disappear. Or it requires letting go of the problem knowing that the outcome of one’s action may transform the circumstances in such a way that the perceived problem becomes irrelevant.