"The usual conditions" means repentance and confession of sin, asking the mercy of God and with a firm purpose of amendment, i.e. to correct the wrongs done --- if it is in your power---- and, with the help of God , to sin no more and avoid the near occasions of sin.
If a person thought he was pulling the wool over God's eyes by confessing without repentance and asking for indulgence without any intention of truly turning away from sin, that person would be a fool; and he would be offending God yet again with his trifling or sacrilegious attitude.
I think any reasonable person could see this.
Then why do people in the roman church go to confession every week????