This penalty:

https://www.eitc.irs.gov/tax-preparer-toolkit/hot-topics-for-return-preparers/news-and-updates-for-p...

"A penalty under Internal Revenue Code section 6695(g) for each failure to be diligent can be assessed against a paid preparer.

For returns and claims for refund filed in 2025, the penalty is $635 per failure to be diligent."

If it's worth $635 to the IRS for me NOT to be diligent, it must be worth at least that much to the taxpayer for me to be diligent.