Muslims observe Roza (fasting) during the month of Ramadan because it is one of the Five Pillars of Islam, which are the core practices of the faith. The primary reasons for fasting include:

1. Obedience to Allah – Fasting in Ramadan is a commandment from Allah, as stated in the Quran (Surah Al-Baqarah 2:183):
   “O you who have believed, decreed upon you is fasting as it was decreed upon those before you that you may become righteous.”
2. Spiritual Purification – Fasting helps Muslims develop self-discipline, resist temptations, and cleanse the soul.
3. Developing Taqwa (God-consciousness) – By refraining from food, drink, and sinful behavior, Muslims strengthen their awareness of Allah and become more mindful of their actions.
4. Empathy for the Less Fortunate – Experiencing hunger and thirst reminds Muslims of those who are less privileged and encourages charity and gratitude.
5. Seeking Forgiveness and Rewards – Ramadan is considered a month of mercy and forgiveness, and fasting is believed to bring great spiritual rewards.
6. Following the Example of Prophet Muhammad (PBUH) – The Prophet Muhammad emphasized the importance of fasting and taught that it leads to moral and spiritual growth.
7. A Time for Prayer and Reflection – Fasting is accompanied by extra prayers, recitation of the Quran, and acts of worship to strengthen faith.

Overall, fasting in Ramadan is a way for Muslims to purify their hearts, increase their devotion to Allah, and grow as individuals.