I met a friend a while back. He was coming back after getting his watch repaired. Here’s the conversation we had:
Friend: the businessman was stupid?
Me: why?
Friend: when i went to the shop this guy said he would charge me 250 for the repair. Today he told me that it actually cost him 550 rupees but since he had committed 250, hence he would charge me only that much.
Me: (interrupting him) Wow!
Friend: wow? How stupid!!!
We didn’t pursue the conversation any further. While I was thinking, what great integrity, my friend must have been thinking what a stupid businessman. I think both of us are thinking right. Lets see how.
Stupid businessman: Ideally he should have said something like, “I am sorry, I underestimated the issue and the part that had to replaced was way expensive than what I had thought. It actually cost me 550 bucks so it would be nice if you could pay me the same.” My friend would have argued a little and maybe after some fuss he would have given 550 or maybe negotiated for 500 lets say. The business of a business is to do business. Which means he should not suffer a loss knowingly and should make every possible attempt to assure profitability for his business. Perfect business sense. But since he did not do so, hence a stupid businessman.
My opinion: By telling the truth and still not asking for the extra (actual) money, the businessman showed his integrity. For him his integrity mattered much more than 300 bucks! If I was there instead of my friend, I would have insisted and paid him the entire amount, not sure whether he would have accepted it. More importantly, I would have shared the incident with other friends and would have recommended in case they were looking for watch repair shops (in the same vicinity). Actually, I have still shared the story and would still recommend 
Like The Bhagwad Gita says, there are no right or wrong answers, there are only perspectives.
What’s your take? What would you have done?