Introduction:
In the story "The Summer of the Beautiful White Horse" from Class 11 English NCERT Solutions, written by William Saroyan, the horse is stolen due to various circumstances. The story revolves around two young boys, Aram and Mourad, who come across a beautiful white horse and develop a deep affection for it. However, they soon discover that the horse is stolen, leading to a series of events.

Reasons for the Theft:

1. Poverty and Desperation:
The primary reason behind the horse being stolen is the poverty and desperation faced by the thief who steals it. The story is set during the Great Depression, a time of economic hardship. The thief, Ali, steals the horse in the hope of selling it to improve his financial situation and provide for his family.

2. Lack of Moral Compass:
The thief's act of stealing the horse also highlights a lack of moral compass. Ali does not consider the consequences of his actions or the impact it may have on the rightful owner. His desperation blinds him to the ethical implications of his decision.

3. The Symbolic Value of the Horse:
The horse, being a beautiful and rare white horse, holds symbolic value. It represents purity, freedom, and innocence. The thief may have been drawn to the horse's symbolic significance, making it a desirable target for theft.

Consequences:

1. Emotional Impact:
The theft of the horse deeply affects Aram and Mourad, who had developed a strong emotional bond with the horse. They feel a sense of loss and betrayal, unable to comprehend why someone would steal the horse they had cherished.

2. Moral Dilemma:
The theft also puts the boys in a moral dilemma. They are torn between their affection for the horse and their sense of right and wrong. They struggle with the decision to reveal the truth about the stolen horse to their uncle or protect Ali, whom they sympathize with due to his poverty.

Conclusion:
The theft of the horse in "The Summer of the Beautiful White Horse" is a result of poverty, desperation, and a lack of moral compass. It leads to emotional turmoil for the young boys and raises moral questions. The story explores themes of innocence, morality, and the choices individuals make in difficult circumstances.