A successful person means he must be good and eligible to do any type of task with his thinking ability. so obviously, he must be good. a successful person doesn't mean a politician winning in elections etc. so, as per me , a successful person should be good in his thinking, mindset
No, successful people are not always good. we do not know that person's nature , thoughts and mindset. Also these days there are many cases of verysccessful ppl bein indulged in wrong things , so we can't trust them. And usually what looks filtered always has some dust and of course no one is perfect.

you can elaborate this, and plzzz mark this answer as the best.