"massive reason" is a correct and usable phrase in written English.
It means a very significant or important reason. Example: The team's loss in the final game was a massive reason for their disappointment, as they had worked hard all season to reach that point.
"But there's no massive reason for that slight loss of form.
The impact Japanese has had on the wider local community was a massive reason why I won the teaching award.
"I know Sam from Newcastle and he was a massive reason for me coming," added Carroll.
Youth turnout was a massive reason for Labour's late surge denying Theresa May her majority, with early estimates suggesting 72% of 18-to-24 18-to-24 18-to-24having learned their lesson from letting grandma decide Brexit.
That said, it appears that a massive reason that Amanda's video has gone viral is because of the story of her husband, who has a degenerating disease that caused him to lose his vision.
Massive beyond reason, Brobdingnagian, my field guide, tells me that these amphibious giants are second only in weight to the elephant; cranky, ornery, extremely dangerous, shockingly fast, and now I'm told empathetic to other non predatory animals (or at least so at times).
It's massive for a reason.
It is, however, a massive mistake to reason from the converse, by holding that any general and neutral policy should pass constitutional scrutiny as a matter of course.
The reason massive security disasters hit almost weekly these days is because for twenty years virtually the entire industry has, tacitly or explicitly, chosen the latter course.
MASSIVE QUEUE Another reason not to bother.
The reason massive military spending is considered the most "obvious" way to produce a fiscal stimulus is simply that it is the only form of direct government spending that gets a pass from the deficit hawks.
