Google accounts are not intended to be used by multiple people, and there are restrictions in place to stop this from happening. Namely, when there is aan unusual log-in attempt from an unrecognised device, especially if it is in an unrecognised location, Google will automatically require two-factor authentication, using the mobile phone that is associated with the account. Depending on the severity of the security threat, Google may also implement further measures to make it harder to log in, such as requiring the user to select the number displayed on the phone (out of three numbers), and further steps involve captcha screens with visual and even auditory challenges. These further steps are typically implemented if behaviour similar to a bot is detected.
In short, sharing a Google account with others is problematic. Even though it is possible, it is a security risk, hence, most people shy away from doing it.