Mr. Bumble did not think much of Oliver Twist. He is responsible for naming the infants that are born into the parish without parents, so he names him.
We name our fondlings in alphabetical order. The last was a S,--Swubble, I named him. This was a T,--Twist, I named him. (ch 2, p. 6)
Mr. Bumble tells Brownlow that Oliver was not just a foundling, he was “born of low and vicious parents” and was a bad one all his life. In fact, Oliver was bad from birth!
[Oliver] displayed no better qualities than treachery, ingratitude, and malice. That he had terminated his brief career in the place of his birth, by making a sanguinary and cowardly attack on an unoffending lad, and running away.... (ch 17, p. 86)
Fortunately, Brownlow is intelligent enough to know that none of this is true. He eventually takes Oliver’s true character as evidenced by his actions since living with him. The boy is nothing more than a victim of circumstances.
In the end, Oliver gets to live the life he deserves, in a nice family--and a rich one!