CSV Import Performance

I import a csv file with 500 lines. A flow is triggered (collection create) to check the line values.
Currently, processing takes approximately 1 second per line. A row passes through several flows, checks each value against database entries, and identifies data errors.

This import takes approximately 10 minutes…

Does anyone have ideas on how to improve performance?
Which operations are time-consuming?
Does the number of operations and flows matter?