The IRS reviews tax returns for many reasons including totally random checks.
Since in 2018 studies shows that TurboTax had 70% of the online do-it-yourself tax market, it only stands to reason that the vast majority of people that the IRS checks used TurboTax, even if totally random.
Heck, when 2 out of 3 people use TurboTax then TurboTax customers should be checked more often - if they were not, then the IRS would be accuses of favoring TurboTax customers :).
**Disclaimer: This post is for discussion purposes only and is NOT tax advice. The author takes no responsibility for the accuracy of any information in this post.**
