After finishing my prayer and before leaving the mosque, I do a prostration during which I pray Allah for mercy and other things.
Some people object.
Such a prostration, or sujood, is neither necessary nor recommended. We do a prostration of gratitude to Allah when we hear some good news. We also prostrate ourselves at the time when we read or hear certain verses of the Qur'an which mention prostration in submission to Allah. Apart from this, no separate or individual prostration is recommended.