How to work productively?

I note first making efforts again and again to get work done increases the self-esteam of the relevant person. 

However, I noted two methods competing.

One is time spent on working serves as an indicator of how productive someone is. So that one works, under this supposition, long hours despite having desire to rest, but he refuses to rest and continues to work. Under this method,  one works long hours but the quality of work done is not high.

The second method is one rests but does not rest too much, again and again, yet one works long hours. Under this method, one works when one is able to do a quality work. The rest of the time one prepares himself to get work done. Simultaneously, one increases time done quality work by working hard. So that one may develop muscles for getting more quality work done. 

There are times when you do a work, you don't need to do it again. It is done forever.