No matter in physical or cyber world, there are facilities built for people using them to achieve certain purposes – whether paid or free.
All these facilities are designed per proper usage. That said, if the assumed usage behavior is not exercised, some adverse consequence might be resulted to the facility provider or the facility user.
Take Internet banking as an example. Banks always remind people to safeguard their access credential (i.e. password) to avoid account being misused: never disclose the password to 3rd party not even the Bank, mandate 2-step authentication, enforce regular changing of password, never click links from email or from social network shared by others. Further, the Bank will alert account holder via text message or email for any credit card transaction executed with physically wiping the card, impose transaction limit to 3rd parties, etc.
So as an user, do the right thing as advised to keep cyber secure. That means in the Internet banking example, you have to provide up-to-date contact information, follow the guidance from the Bank to secure your account from misuse.