I've heard Christian after Christian worry about their praying; whether they do it often and sincerely enough. They may describe prayer as their weakest suit in their Christianity. This depresses me. It's a inevitable result of there being an activity which is praised from all corners, yet whose process is rarely specified, whose techniques are disputed from one practitioner to another, whose results are predicted to very different degrees of confidence, then inevitably rationalized. Not to mention the discrepancies in different prayers’ experience — some people simply lack the “talking inner voice” or “inner other person” which others have. When you reify that voice into something more, into an actual deity or Spirit, it’s as if the same person loves talking to all those people but for some reason ignores you. It’s like feeling bad about yourself for not having flying dreams. Why can’t I fly? Am I not trying hard enough? And the worst of it is that some of the people who do experience the voice insist that indeed, you’re not trying hard enough.
There exist Christians who lambaste one another for praying incorrectly, and there are those who tolerate pretty much the entire gamut of praying-related attitudes — except, perhaps, the smiling affirmation of not praying at all. One finds contempt especially for the notion that prayer is no different than what it would be if God didn't exist, ie, prayer is not any kind of connection to God nor anything that God remotely cares about, it's just a kind of talking to oneself or (when spoken publicly) to other human beings. (This notion, interestingly, is almost synonymous with atheism, rather like how the disbelief in an omnimax god can be synonymous with atheism. In both cases, God can be defined in other ways, but usually is not.)
Come to think of it, it's rather like conventional attitudes about food. People get into tense debates over what they and others should and shouldn't eat (on grounds of taste, nutrition, and culture), while still other people accept the existence of every imaginable diet — but there's a definite consensus that everyone ought to eat something, if they want to be a healthy, complete person. And people can feel stressed that they’re not eating right, but I don’t think it’s as frequent. A key difference is that our understanding of food largely reflects the evidence (especially the conclusion that it is necessary for survival). And unlike with prayer, one can adjust one’s diet in accordance with the experts without finding nearly as much disagreement among them. (Well, maybe the same amount of disagreement, but perhaps that’s owing to the sheer diversity of food.)
I don't really think there's any solution to the problem except to advocate the attidute I described earlier: Prayer simply doesn't matter. Isn't that wonderful? (And supposing God does exist, wouldn't that make so much more sense, as other atheists have pointed out?)