Keep on taking backup even when Max backup is defined

[abhishekakt1]

Hello

I am having issue with max number of backup. Here's my current setting:

I want to have 3 backup copies and full backup on 4th day but it keep on taking backups. My understanding is that every 4th day (as max # of backups is 3) , it will delete first old backup copy. However that does not seem to be the case:

Can anyone please help?