Enterprise addresses carry no stake rights, so using these addresses means that you are opting out of participation in the proof-of-stake protocol.
Exchanges or other organizations that control large amounts of ada – but hold it on behalf of other users – may wish to follow a policy of not exercising stake rights. By using enterprise addresses, exchanges can demonstrate that they follow this policy. Since enterprise addresses are not associated with any staking key, they are automatically excluded from the mechanisms that influence the slot leadership schedule. Note that using addresses with no stake rights effectively decreases the total amount of stake, which plays into the hands of a potential adversary.