Nusach Ha-mikra – Accuracy of the Biblical Text
⬇ Source sheet (PDF)
The Masoretic version is indeed accepted as authoritative, but since the Tanakh is such a remarkably complex work, including tens of thousands of details - letters, vowels, cantillation marks, etc. - in many instances the general acceptance of an authoritative version was not sufficient for it to be implemented with perfect accuracy throughout the Jewish Diaspora.