What do you think about this assertion by the late Bob Proctor?

All I like to say is that it reminds me of what Henry Ford once said:

"Thinking is the hardest work there is, which is probably the reason why so few engage in it."

To me, it's one of the most crucial cognitive skills one can develop. 

By practicing well-thought-out thinking, both our thoughts and decisions can make a positive change in our life, on both a professional and personal level. We can hugely improve our life by working on our critical thinking skills as often as you can.

Nevertheless, here's a nice comment from IT expert and philosopher Anand Damani:

"Thinking is never hard but a natural function that is always happening. Thinking is an activity done by one of the subatomic particles of the life-atom. 

It is a precursor and a prerequisite for any action that a human being can take. 

It is an activity that every human being is always doing. 

Being endowed with the power of imagination, human beings can keep thinking of anything and make their perception a reality that may not actually exist. 

Aligning thoughts with the actual reality is the purpose of life."