The most common reason is missing guest e-mail on PMS.
Accessing Analytics you will see how many guests you are engaging.
As the example above, only 84 of 1131 guests could be reached.
You are losing the opportunity to contact / make up-sell with 1047 guests, meaning a loss of 92,6%.
- Collect OTA's e-mails and introduce on the PMS.
- Collect emails at check-in process and introduce on the PMS in time.