Why are so many people who filed with TurboTax under review?

[Techisam]

I see a very large majority of people online and social media under review and the large majority of them filed with TurboTax. Don't give me some generic answer either. I've heard from a few that TT didn't submit all the info correctly on their returns. ANSWERS PLEASE!

[CarissaM]

Only the IRS knows why they select the returns they do for a review. 

In order to determine the exact reason, you will need to contact the IRS to see why your return was selected for a review. 

[macuser_22]

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 :).