The question concerns the planning stage, which is what fixes the order of the steps, and at that stage a review of the existing literature comes first.

Being familiar with the literature on the topic is essential for several reasons at once. It establishes what is already known, so that effort is not spent rediscovering settled findings. It reveals the gaps in existing knowledge, and the research gap is what justifies a new study at all. It shows which theoretical frameworks and which methods other researchers have used and how well those worked, which informs the design of the present study. It supplies the concepts and definitions the field uses, so that the new work speaks the same language. And it helps sharpen a vague interest into a researchable question, which is often the hardest part of planning. For all these reasons the literature review is placed early in every standard account of the research process, after the broad problem is identified and before the design is settled.

Doing a pilot study is genuinely good practice, and it is the strongest of the distractors. But a pilot study tests instruments and procedures that have already been designed, so it comes after the literature review rather than before it. One cannot pilot a questionnaire that has not yet been written.

Approaching the topic with an open mind is desirable in the sense of avoiding prejudgement, but taken as advice it is not helpful at the planning stage and is sometimes read as an argument for ignoring prior work. Openness to what the evidence shows is compatible with knowing the field, not an alternative to it.

Forgetting about theory is simply poor advice. Theory guides what to look for, what to measure and how to interpret findings; research without it produces data that cannot be made sense of.

Hence when planning social research it is better to be familiar with the literature on the topic.