Is hard work the key to succeed, or doing a smart work?

There is a bit difference with hard work & Smart work, but Pre-pan and calculating time is essential for smart work, I am working smartly, it reduce work load. 

Hard work is the only key to achieving it; it teaches us discipline, dedication and determination. Hard work is definitely more important because it is only through hard work that we can achieve the goals of our life. Smart work, on the other hand, often leads to shortcuts and procrastination.

I think both are important because when we work hard we will get smatness in what we are doing 

POSITIVE ATTITUDE. Positive attitude comprises both smarts and determination. If one works hard but not conscientiously, like stepping on his/her colleague's rights, then he/she is only being a burden to others, and the other ones become affected in their work. On the other hand, if one works smart but insensitively, like instead of sharing his idea of how to do things efficiently, he is only being an extra baggage to his colleagues. But if one has positive attitude, he/she will strive and let know how to get the right things done. 

The smart work is always the correct work, considering a type of work is a hard work or smart work depend on your definition of the work.