To start with, being hard work does not always implies being successful. In other words, not all hard workers are successful. However, the larger percentage of people who are hard work have been successful in their various fields or areas of specialisation. Nothing good comes by easily and success is not served on the plate of indolence. Therefore, to be successful in life one needs to be more determined and hard work, especially in my country.
Meanwhile, one can be hardworking but at the same time using one's energy in a wrong way, and as such could draft far away from success. For instance, a man who has never being to school and could neither write nor read is preparing hard for an interview as a professional, wrong! He should have directed his efforts to his area of expertise. An effort channelled in the right direction will always yield multiple results.
Although, hard work putting on a particular task may not bring results immediately, it will certainly bears enormous fruits. There are many examples of people who have put extra push on their careers or areas of specialisation. Such people include Christano Dos Santos Ronaldo (CR7, Zinedine Zidane, Michael Phelps, Usain Bolt)
Further more, hard work put in on educational career also reflects on the results most times.
Also, in order to succeed, many have resolved to involving in more than one career. I, personally embark on "after office task" in order to be successful or comfortable. Though it may be tough, though it me uneasy, though it may seem odd, yet it's the best I can do to make my family great. Not only do I bring food on my family's table, I contribute to the country's GDP.