Crying during دعاء is a praiseworthy sign of a humble heart, but not crying does not mean your دعاء is rejected — sincerity of heart matters more than outward tears.
Crying during دعاء is viewed positively in Islamic tradition as an expression of humility, awe, and genuine connection with Allah. النبي (صلى الله عليه وسلم) mentioned that among those shaded by Allah on the Day of Judgment is 'a person who remembers Allah in seclusion and their eyes overflow with tears' (Bukhari and Muslim). At الحج, especially during the standing at عرفة, the emotional intensity of the experience — combined with the awareness of Allah's mercy and one's own shortcomings — naturally moves many الحجاج to tears.
However, scholars are careful to emphasize that not crying does not indicate a rejected دعاء or a hard heart. What matters is the sincerity and humility in one's heart, not the outward manifestation of tears. Imam Ibn al-Qayyim noted that sometimes a دعاء made with a quietly present heart is more beloved to Allah than one accompanied by dramatic weeping. Do not force tears or feel spiritually inadequate if they do not come — focus instead on being genuinely present with Allah in your الدعاء. Some people express deep emotion through quiet concentration rather than tears, and that is equally valid.
Source: صحيح البخاري; صحيح مسلم; Ibn al-Qayyim, al-Jawab al-Kafi