Hi Sameer,

As per PDN help

A likelihood is a value between 1 and 100, interpreted as an assumed or known probability associated with a flow action. For example, a likelihood of 66 on a flow action labeled Accept means that users completing an assignment linked to that flow action are expected to choose the Accept flow action two out of three times.

When editing a flow in Process Modeler, click the percent sign icon to display likelihood values.

You can refer article : https://docs.pega.com/directing-percentage-work-specified-processing-path for better understanding of how it works.

Regards,

Shanthini Charles