The standard B2B case study opens with a company description, moves to a vague challenge, describes a solution, and closes with a percentage nobody can verify. Almost nobody reads past the second paragraph, including the buyers it was written for.
Lead with the number
If the result is worth writing about, put it in the first sentence. Not in a pull quote, not after four paragraphs of context. Readers decide in seconds whether the outcome is relevant to them, and making them dig for it loses the ones who would have kept reading.
If you do not have a number worth leading with, you do not have a case study. You have a testimonial, which is a different and shorter format.
Name the starting position
Vague before-states make results meaningless. Conversion improved by forty percent tells the reader nothing without knowing it went from one percent to one point four percent, which is a very different claim from twenty to twenty-eight.
Buyers in India are appropriately sceptical of unanchored percentages, because the market has seen a lot of them. Absolute numbers at both ends buy credibility that percentages cannot.
Include what went wrong
Every real project has a part that did not work. Including it is the single largest credibility gain available in this format, and almost nobody does it because it feels like admitting weakness.
It reads as weakness only in a document nobody believed anyway. In a case study with specific numbers, a paragraph about the approach that failed first makes the rest believable.
A structure that works
The result in one sentence. Who the customer is and why their situation resembles the reader. What they tried before and why it did not hold. What you did, specifically enough that a competent person could attempt it. What did not work. Where the numbers landed, with both start and end. What the customer said, in their own words rather than marketing-approved ones.
The length question
Shorter than you think. Eight hundred words with real specifics beats two thousand of narrative. The people who need more detail will ask, and that conversation is worth more than the extra twelve hundred words they would have skimmed.