What are the consequences of infusing a tea bag longer than recommended? I'm a regular consumer of tea (since about 2 years ago), usually from commercial tea bags.

They advise to infuse tea for 3 to 5 minutes, but there is some times that I have left it longer by accident.

So I have been wondering what are the consequences -if any-  of infusing tea bag longer than recommended by sellers (sometimes up to 10 minutes). My question is general, but I'm especially interested in black tea.
The tea will be stronger than you'd like if you steep it for too long. Over-steeping sometimes gives a bitter flavor as well. (I am guilty of frequently over-steeping as I have the attention span of a goldfish. Sometimes I remember to set a timer, sometimes not.)