The hard part is usually in the execution.

Problem solving usually involves experiencing discomfort.

The ability to push past discomfort is key to solving non-trivial problems. Like a muscle, this ability improves with practice.

The problem could be to lift a heavy weight or to solve a hard coding question. Either way, there is certainly much to be gained from having the right understanding and approach but successful execution is mostly the end result of having a long consistent history of smaller successful executions.

Sun Tzu: "Victorious warriors win first and then go to war, while defeated warriors go to war first and then seek to win. "