Users of e-commerce services are buyers or sellers and the goal is to facilitate transactions between them with trust and reliability. However, a series of events may make those transactions unsuccessful.

Among other things, orders fail due to issues with payment or fulfillment. Some of these reasons are reported in the Table below.

# Reasons
1 Items do not arrive.
2 Items do not match the description.
3 Items are damaged.
4 Payment processing failed.
5 A payment is a fraud.

In turn, it appears crucial to monitor KPIs that provide an accurate snapshot of
how well the e-commerce service fulfills the transactions because failed transactions make users of e-commerce services unhappy. If failures repeat,
they will lose trust, which will affect the performance of the business.