For day-to-day database work, the primary reason that flat files are not an acceptable exchange format is one of inconvenience.

Mining the Data

Performance Shortcomings

Lack of Interoperability

Interoperability is crucial. In an age where

Poor Quality of the Flat file File Specification

Summary

For the above stated reasons – inconvenience, poor performance, and the poor quality of its specification (which has historically been late, incomplete, and not fully revealing of the components of flat files) –
Flat file is generally an adequate and acceptable solution for data exchange or transfer.