There is special pleasure we have when planning to complete a task and then completing it. The Rosh Yeshiva ztz"l explain that this is because the only being in creation who came into being after being planned was man. Everything else was just created but when it came to man it says first "נעשה אדם" - let us make man and only then was he created. From that time and on man has special pleasure when he plans and executes b/c that concept is built into him.
This is also true biologically. Dopamine is a neurotransmitter in the brain, that motivates us to take action toward goals, desires, and needs, and gives a surge of reinforcing pleasure when achieving them.
People enjoy completing tasks because performing a task to achieve a goal generates dopamine within the brain and then the completion of the task creates another rush of dopamine. It's one of the bodies built in motivational mechanisms and effectively provides a happiness hit.
Mussar Haskel: Plan and execute!!! 😀😘
