One of the first decisions when setting up professional email is: how many accounts should you get? Getting it wrong is costly either way — too few accounts jams up your team's workflow, too many is budget wasted on space nobody uses.
Instead of automatically creating an account for every single person, think in terms of roles. A small business usually needs: an account for each person who deals directly with customers, role-based accounts like contact@ or finance@ (which can be shared or forwarded to several people), and maybe one account reserved for automated notifications from your systems.
A 2GB mailbox is plenty for most people who mainly exchange text-based messages day to day. People who regularly send large attachments (contracts, images, spreadsheets) benefit from a bigger inbox. Mixing different sizes within the same plan — instead of paying for the same "large" space for everyone — is the most efficient way to avoid paying for space nobody uses.
The ideal number of accounts changes over time. The advantage of a flexible provider is being able to adjust — add, remove, or resize accounts — as your team grows or changes, without being locked into a fixed package you signed up for a year ago.
The secret isn't "more is better" or "less is cheaper" — it's sizing things to exactly what your team actually uses.