It's wrong to point out another person's flaws.
Suzy was having an argument over money borrowed by Lisa, who is known to have blown money in the past.
Suzy wants to end the argument.
Suzy doesn't mention Lisa's past, but points out that Suzy really needs the money back.
Suzy points out Lisa's irresponsible past and says Lisa will never repay because of it.
Lisa pays back the money as soon as she can, and the two patch things together.
Lisa becomes resentful of Suzy and never speaks to her again.