My son is 8 now but use to do that at 4/5 and on. He was craving my attention and I was giving it to him. It prevented him from becoming more independent. When children go to school and see other children doing things without help, they will do or work towards the same. Socialization and competition with peers. There is a point when helping is good, and then it is done so much it becomes harmful.
This can lead into laziness on your child's part because they have found a way for "someone to do it for them." You must break this pattern.
ie: my son would not dress himself, but I would lay out his clothes the night before. so on the weekend, if we were headed somewhere, we would miss a couple of functions until he started getting ready by himself to make these function. or we would get to the function late, but he was able to understand what he had to do to be places he wanted to go on time.
ie: we had to do reading. started out reading 3-5 pages, until we could read 20 minutes. he would say he did not know, but I knew the words were very familiar to him. so, I would go over the words then start him reading. i would tell him we could move onto the next activity when his reading was complete. I would do other things and have him get me when he was ready, but he could not get any of his other privledges until this was done.