Its what people do to make themselves feel good about doing something without actually doing anything.
Example.
If there is a drought in Africa and people are starving, in churches all over the land, people will pray for Africa.
'Dear god, please help those poor starving people in Africa' they will pray. The, they will go home feeling good about themselves because they just 'helped' the people of Africa by praying...except they didn't help at all, people still died.

What they could have done is sent money for food, or gone out on to the streets collecting donations and arranging fundraising events, but no. Most people wouldn't do that because it takes time and money and real effort.
No, they would just say a quick prayer and then bask in their own self-righteousness.

The worst example I think I ever saw of this is when there was a huge and terrible storm in the Philippines. Thousands were killed and they interviewed one lady on TV who had a lucky escape. The first thing she said was 'I prayed to god and he saved me from death.'
I'm sure all the others prayed too to be sved but weren't. What disgusting selfish arrogance to thank god for yourself whilst not blaming him and forgetting about all those who weren't saved.

The final thing about prayer is that it's also often selfish.
'Please god let me have more money...get well....win the lottery'
Its all about me, me , me.....and surely the bible teaches that selfishness is a bad thing?

Contradictory, no?