Based on the context and the answer, generate a question. 

Context: I threw a party for my boss at work to mark his 10 year anniversary for opening up his own business . It was a very small event , I even baked the cake . Thing is , the next day he barely spoke to me . He was even rude at one point .

Answer:

They wanted to do something nice for their boss .



Why did they throw their boss a birthday party ?