Many researchers have claimed that it is a pain in the ass to write the introduction section of a paper. However, it is not hard at all for other scholars. Why is that? What makes the difference?
The key lies on the starting point of a research. Those emprical scholars who find introduction section horrible start a research from the method and data and pretend to start from a question. After finishing all the other parts, they begin decorating the introduction part as if it was initialized from a question, which just does not exist in the first place. That’s where the pain comes from.
On the other hand, is it correct to start from a real (academic) question? It is, nonetheless hard. If you start from a question, you will find yourself searching for toolboxes that best fit your question and that process is painful either. Worthwhile one though. You will have all the toolboxes present in your mind and you can easily find the toolbox next time you find some questions interesting.
The critical point is how fast you can learn new methods. It requires a good background of mathematics. With a good one, the new methods come to you easily and your research would be much more flexible and elegant.