I am pulling these out of my 4$$ but all of the normal things you could get a bad review over would apply. A portfolio company's respected founders (basically,

I am pulling these out of my 4$$ but all of the normal things you could get a bad review over would apply. A portfolio company's respected founders (basically, your client/customer) saying that a partner was difficult to work with, making poor suggestions, wasting time with questions they could get answers for elsewhere, or embarrassing them in meetings with important contacts, etc. Another partner saying that you are difficult to get along with, argumentative, do not do proper research, miss glaring information that demonstrates high risk in an investment, and so on. Basically, doing a shitty job, being difficult to work with, ruining the firm's reputation, and/or making very bad investment decisions would be good ways to get a bad review.