Maricopa County, Arizona found 420,987 FAILED ballot envelope signature verifications in the 2020 election. Maricopa County, Arizona alone had a total of 2,089,563 million ballots. 1.9 million of those ballots were by mail.
Mail-in ballots were used as a main method of fraud, not just in Arizona, but around the country. Now you understand why mail-in ballots must be banned, except for reasonable exceptions, to eradicate fraud and maintain election integrity. Trump won in a landslide.