What is Business Verification for WhatsApp?

You only need to complete business verification if you:

1. Need to connect more than 2 phone numbers
2. Need to have more business-initiated conversations w/ >50 users in a rolling 24 hr period
3. Need OBA (official business account - green check mark verification)

This means that you can have unlimited user-initiated conversations without completing business verification.

WhatsApp performs a Platform Policy account check to ensure the account and its intended usage comply with its policies.

For more information on the benefits of business verification, see this overview.