Does Every Fictional Character need Character Development?

[DEEcat98]

Do any of you think every fictional character needs character development?

[Silverwing]

No.

[flemishcap]

Of course not, lol.

A background character walking across the street doesn't need any character development. 

[timmelon]

A background character walking across the street doesn't need any character development. 

Although FiM fandom could make a character from background pony .

Personally, I was not so close to this fad, and, for me, «The Last Roundup» episode was more about «Picklebarrel-Kumquat-Chimicherrychanga» than «OMG, Derpy just talked!».

[Rainberry]

No not at all.  Some are just meant to be filler and background characters.

[DEEcat98]

Though from what I said before, should a character get character development if his/her mistreated, misunderstood, or sympathy side is being shown? I mean, isn't that hinting on character development?

[Sniffles]

I do not think so.

[electricferret]

Thats a plot hook, not necessarily a promise.

[DEEcat98]

Thats a plot hook, not necessarily a promise.

Well, here is one reason why I am asking this.

One reason why I asked this question is because of how I am regarding to Harvey Girls Forever! (formally called Harvey Street Kids during its first Season). The show ended two year ago, yet with how it lasted for four Seasons, it ended with some unresolved stuff. Why can't the show last longer or at least continue with another series just so that it would start to later focus on character development?