Israel wanted a king (1 Samuel 8)! There were some legitimate reasons why they needed a king. A king would help them to be something more than the loose confederation of tribes that they were—characterized by infighting and the failure to come to the aid of each other when under attack (see the book of Judges). Furthermore, it was God’s intent for them to have a king (see Genesis 49:10 where God is blessing Judah when he speaks of the scepter not departing from them). All of this is to say that their desire for a king was not wrong in and of itself, but the reason they wanted a king was. They wanted a king to take the place of God (v. 6-7).
It’s can be helpful to step back every so often and ask ourselves why we pray for the things that we do. The Pharisees took a good thing (prayer), and used it in a bad way. My guess is they didn’t intentionally start out with the idea of corrupting prayer, they probably drifted into it through a lack of attention (the way some of our problems develop).

Our prayers can take the path of being traditional—we can pray for what we think others expect us to pray for. This can be good or bad depending upon the specifics of the expectation. (I’m obviously here addressing only public prayers). From my experience, our prayers are often titled toward being heavily intercessory for those who are sick.
Why? Probably because this is to many the most obvious thing to pray for. Someone asks for requests before a prayer is led and understandably someone else mentions a person who is struggling with illness. That causes someone else to think of another person, and then a third is brought up, and then someone speaks up who’s feeling guilty for not having mentioned their Aunt Lucy’s husband’s cousin and off we go.
Very rarely does someone go against the flow and speak of praising or thanking God, praying for the kingdom to come, the lost, temptation, forgiveness, etc. By the time we’ve brought all of these people before God, the one leading our petitions is wearied and the prayer is concluded. And while it’s good and right for our prayers to be shaped by our circumstances, it becomes unhealthy if our corporate prayers consistently reflect a single dimension (intercession for sick). Our right arm might be extremely well exercised and toned, but the rest of our body is out of shape. It can also convey the wrong impression—in this case, that the most important thing in the kingdom of God is the health of people (read through the Scripture and be surprised at how relatively little is said about that compared to the emphasis we place upon it).
Closely connected to this, our prayers (individual and corporate), can be influenced by routine. There can be a sameness to our prayers (which is maybe one reason we ask for requests!). Again, the problem is not so much what we’re praying about as what we’re leaving out. Praying the same thing can not only lead to mindless repetition, but keep us away from developing depth.
This is why the model prayer is so helpful. Like a great tree, it branches out in so many directions to continually challenge and develop us in prayer. When the prayer’s framework is applied and accompanied by a life that is involved in service and Scripture, prayer will flow more freely and with fewer dry spells. None of this is to suggest that our prayer life will be free from struggle (Romans 8:26ff says otherwise), only that as in all other aspects of our lives, God wants to enrich and develop us. We should not be satisfied to settle for anything less!