Why were so many citizens of pompeii unable to avoid the disaster?

What happened in Pompeii was a tragedy--the disaster was a strong volcano eruption that coated the city in ash. The ash from a volcano can travel very long distances over a short period of time. Many citizens could not avoid the disaster because of how unexpected it was. In addition, the ash spread faster than many citizens could escape.

The time they found out it was too late and didn't have anyone to go