To determine the likely reason the artwork was created, one would need to consider the specific context and content of the artwork in question. If it's a design for a building, it would suggest utilitarian reasons. If it delves into the artist's emotions, then expressive reasons might be more appropriate. If it features a character intended for a film, it would be for entertainment purposes. Lastly, if it depicts a significant historical event related to a famous castle, that leans towards historical purposes.
Without seeing the artwork, it's impossible to definitively state the reason, but you can analyze the characteristics of the piece to guide your conclusion.