The Saudi Rationale regarding Yemen

Militarily, Saudi Arabia has not achieved its goals. However, to understand the rationale behind the intervention, Saudi Arabia’s actions must be seen in a wider context that includes both its domestic and regional goals. From this perspective, this military incursion serves the present interests of Saudi Arabia in a number of ways, regardless of the military outcome.
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Has Saudi Arabia already won its Yemen war?

It is important to note that for Saudi Arabia, Yemen not having any government at all (sort of like Somalia in the 1990s) would be better than a Houthi Government Controlled by Iran.

If the world understands this they will better understand why Chaos and no government in Yemen might be better for the Saudis than ANY government where Iran has any power at all.

Otherwise, it is logical to assume if Iran controlled a government in Yemen that Saudi Arabia would be forced possibly to attack Iran directly rather than indirectly as a matter of survival ongoing. This may be a fight to the death between Saudi Arabia aligned with all the Sunni States against Iran. Iran is basically alone in this except for Assad, the Iraqi government, and the Houthis in Yemen. They are likely more aware that this is a fight to the death than anyone else at this point.

Also, remember there are 1.1 billion Sunnis worldwide and that Mecca is in Saudi Arabia where many Muslims visit at least once a year.