Do you create a new email accounts when a new staff join you, using their name followed by your domain name? What if the staff resigned , likely that you will disable this email account. and you failed to inform your customers and or suppliers who have been communicating with her that this email account is no more in use and to use another email? 

They will received an returned mail that informed them the email failed to send.

We always recommend that you create a generic email example, finance@your_company.com or sales@your_company.com and make it a group email so that you can have finance_1@your company.com or multiple finance staff or sales staff email account under the group account.

Some users explained that customer service is about personalised your email account. Sure , you can do it. Create a tiffany@your-company.com and let it manage by anyone that is on duty. 

See what IRAS is doing, they have their Jamie there to hear you out. Jamie is non-existent, and Jamie could be anyone on duty that day. So you are not caught in a administrative hassle to inform your stakeholders of a change of email address

We have our support email as support@realtimme.net where 5 support staff email is attached to it so that our users can reach out to anyone of them even when any one is not available that day.