If the backdoor was a hack for easier debugging that got left in, not having it during development could make for a longer more expensive development cycle. In which case
it should have been removed before production.
It could also be intended as a support tool to ease hard to debug solutions remotely. Not having it could make support issues more expensive and slower. Very insecure and misguided (security by obscurity is not security) if this is the case, but not malicious. Just a stupid attempt at saving money. This apparently was the case for another commenter
on a different product.
While it's possible it was placed with malicious intent, there are plausible (and all too common) alternatives that explain it.