All you need do is to find out the fault and start posting good quality content to regain back your reputation and credibility in the eyes of Google.Google fined website because of poor web content, you can not remove the sanctions?
Its permanent until you remove itsanction is applied to the site for how long?
You're right. It usually doesn't work. Once you are get on Google's bad side, you might as well change you identity (literally) and everything about how you deal with them, if you ever want to deal with them again.reconsideration usually does not wok. Build another website and start putting some good content on it.
Are you talking about "thin" content?
If so you need to restructure and improve your site and submit a request for reconsideration