People thrive off of other people's failures = People thrive off other people's failures. Off of = off >>"Of " is not necessary and redundant . They mean the same . Take out the word "of" ,and the same meaning in every sentence will still be there.

Hi! They are two prepositions. Because this is used many times in conversational English, to replace "off of" with "from" would sound very foreign. Here are a few more examples of using "off of": He jumped off of the pier The leaves fell of of the tree He knocked the top off of it I profited off of his purchases One thing I will say is that "People thrive off of other people's failures" can also make sense with out "of," which is why some people will say that this is bad English grammar. "People thrive off other people's failures." Thanks!