Developer finds silent data loss bug after pagination returns wrong analytics figures

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A developer participating in DEV Community's Summer Bug Smash challenge discovered they had calculated the wrong statistics three separate times while analyzing contest entries. The core bug was in a data-collection script that silently treated failed API responses — returning plain text 'Retry later' instead of JSON — as missing records and skipped them without any error or warning. This caused 277 out of 412 fetched entries to be dropped, producing a plausible but incorrect figure of 23.9% instead of the true 18.5%. A separate issue revealed that paginating API results at exactly 100 items per page caused 39 of 422 rows to go missing, a problem that disappeared when using page sizes of 99 or 101. The developer resolved both issues by rewriting the collector to treat unparsed responses as unfetched, introduce retry logic with back-off, and assert full data coverage before computing any statistics.

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