People often ask me why my artwork's style changes, there is no distinct or emerging signature uniquely my own. I gathered some of my past and recent works - paintings and illustrations. I observed they seem not to be related with one another, each work created by a totally different person.
I tried to find any specific "signature" style that relates all my works together. If color scheme is the factor, I think my works are almost always bursting with highly contrasting colors. I also found out that I tend to like simple silhouettes with a single unified composition, every work seem almost poster-like, graphic in terms of layout. But I like each of them unique.
Do we really need to find that one true style? Some painters and illustrators say it helps to have one unique, identifiable style and stick to that no matter what. Probably, the reason to this is because you tend to get a 'hold' of a specific market or audience, and perhaps patrons. It's like letting them hooked on your art. In the advertising world where the art director picks the kind of art appropriate for a project, it's important to have consistent style because they need guarantee that the work commissioned to the illustrator matches their portfolio. Advertising illustration is quite precise in conveying messages.
On a personal view, there will always be an audience for any particular style. I believe no matter how varied your style is, if it's really good and strong, it will stand out and people will get to appreciate your work. But of course, you need to put your work out there and show them to your "market."
For me, style is your own manner of doing things in whatever you do. It's like all the habits you've developed, the tastes you have acquired, the places/images you've seen, or the knowledge you have gained through experiences. It's the way you pick and put together your wardrobe, the way you arrange plates on the table, or the way you fix your hair. In art, it becomes your identity, as such, you can use it to amplify an expression and a voice. Your personality becomes your style: it can't be rock and roll when you love classical. I think style is different from a fad. Instead, it is something very flexible and adapts to current trends. It is changing but is developing. No matter what your style becomes, your voice and vision stay the same.
But why do we need to change styles? Because pattern stalls. We get tired of pop songs after the media hype and saturation. Mannerist paintings and illustrations become predictable and sometimes it brings us to a point where they make us cringe. You get used to your hairstyle then feel old. We don't like to wear single colored clothes nor live in a monochromatic room.
Because we live in a constant state of flux in an indefinite continued progression called time.