We can be a hustler in the good, positive sense, or we can be a hustler in the negative sense.
Part of it depends on attitude. It also is framed by work ethic and interpersonal relationships.
No one wants to work with someone who is only in it for themselves - someone who does whatever it takes for them to come out on top. A person like this is not respected and is given many names - "hustler" being one of them. They are unscrupulous, dishonest, fast-moving, fast-talking. They give sales a bad name. They aren't in sales. They're only doing what they do for the fast buck or the swindle.
Then there's the go-getter, the achiever, the one who's always striving to be better - better customer service, faster closings, more satisfied customers. I think we can all appreciate good, honest hustle that comes from the desire to lead, to set the pace, to work until the job is done. Persisitence, commitment, and all-out, untiring effort are the marks of this hustler.