God gave every Christian at least one spiritual gift with which that person should give Him glory, grow the Christian in faith and fulfill the Christian's purpose. These gifts differ from each other. The Christian works within the will and the grace of God when he or she exercises his or her own spiritual gift. The opposite is true when the Christian tries to exercise spiritual gifts he or she doesn't have.
For example, I am a pastor. I do not have all the spiritual gifts. Scripture indicates that is the way that God intended. However, someone can come to me with the expectation that I will exercise a certain gift. I will, unfortunately, try to accommodate them. The result will be disastrous. I am viewed as one who didn't put enough effort into the task. The problem was that the task took a spiritual gift that I didn't have. I tried to act outside of what God wanted me to do. I, therefore, reaped the benefit of learning a lesson the hard way.
Very few pastors have the spiritual gift of leadership. They, however, are expected to have it. We sometimes are so full of pride that we can't admit we don't have it. Churches often arrange their whole structure around a pastor being the leader when he may be the most excellent preacher and Bible teacher that the church would ever know but really stink at leading. He should have rejoiced in the gifts God has given him and admitted to being deficient in the ones God hasn't.
Often people with the gift of mercy will be asked to lead committees at church. They may not have an organized bone in their bodies. They do not like taking stands on issues. They do not know how to organize the meetings, much less the tasks that will follow the meetings. They are frustrated and vow to never serve on any more committees.
Can you imagine what a Benevolence Committee would be like if all of the members had the gift of prophecy. They would be telling the people coming for help how they got themselves into the trouble they are in. They would be demanding repentance before any help would be given. They would be rather cold toward the explanations of those they were helping. Very little help would be given. The prophets would be frustrated too.
Can you imagine someone with the gift of mercy being asked to teach on a topic in which they know very little. They don't necessarily like research but they do like giving people comfort. In the end the people being taught don't know any more about the topic than when they started. They will know there is someone who cares for them. That won't help people learn what they need to know.
Let's suppose someone spills milk in the cafeteria. The prophet will point out that the glass was placed in the wrong position. The servant will clean up the spilled milk. The teacher will show them how to place the items on their tray so that it is efficient and safe. The encourager will tell them that they will soon be able to have unspilled milk meals. The giver will buy them another glass of milk. The leader will organize the whole group of gifted people to help. The one with the gift of mercy will give the milk spiller a hug. Take any of these people and put them in any of the positions in which they are not gifted and they will be frustrated.
Most people already know how they are gifted. Sometimes they don't want to admit where they are not gifted. Therefore, they keep trying to act in a gift that is not theirs. Having been terrible at it in the past is no deterent.
So exercise the gifts that you have with glee. Refuse to try exercising gifts you don't have. The body of Christ is made up of many parts. No eye should act like a foot. No arm should act like an ear. We are what we are. That's how we all fit together.