Knowledge Vs Grade

Yeah I know its an old debate. Probably as old as the education system. But the reason I talk abt this is that I have been caught in this dichotomy oflate. I have been a student of its-grade-that-matters school of thought till the time I completed my engineering. The fact that I was ranked second in the class with more than 80% of marks will vouch for my claim made earlier. Not that I did not have knowledge. And then I joined the industry , so did most of my batch mates many whom did not have so called 'good grades' in their kitty. But they found a place in the industry never-the-less. The day I joined the industry n till the day I left to become a student again, not a single soul enquired of me abt my performance & rank in college. They didnt care. It didnt matter either. The grades I got in the college was of no use unless it has bearing on my productivity in tasks undertaken by me. Meanwhile, I recieved news of some of my lesser-known classmates getting placed in good companies , bagging abroad assignments, drawing hefty salary, in shortdoing good in the industry. This brings me to some questions. Does good grades imply deep knowledge ? Is knowledge the only determinant of a person succes in this world whichever industry he is in ? Is there any thing called 'situational factors' which play a role ? This are important questions. Unfortunately there are no definitive answers to this questions. Every individual during his course in life finds the answers to these questions, albeit in a hard way. Thats how life goes. Accept it and move ahead.