You said Smileless2012, that you prayed for people and their/your prayers were answered.
So suppose those people didn't have any friends like you who were willing to pray for them, and they didn't have any faith themselves that led them to pray.
If they had a terrible illness, for example, was it the praying that helped them recover? If so, then God looks at people who pray to him and give him worship as more worthy of saving than those who don't. Is that the case?
If they were praying for something else, say the safety of a loved one in a war zone, did the praying actually help the person they were praying for? If the person next to them was an atheist, and they died, is that because God didn't hear anybody praying for them and so let them die?
Were they praying for a bigger house? Then that's just trivial.
It just doesn't bear any scrutiny, IMO. Especially if the prayers don't come true and somebody says something trite like "God moves in mysterious ways"