"I don't understand why people
<insert words here> products that have a reputation of hardware failures."
What is the correct way to form this sentence?
This is the correct form:
See 15th definition of buy on Dictionary.com:
There is also a slightly more metaphorical, but not uncommon, sense of this phrase, listed in thefreedictionary.com:
Buy-in is a noun, meaning:
To buy into something, a verb, means:
It would be possible to write your sentence with "buy in to", but this is not common:
Note that this search includes transcripts of spoken English as well as various written sources; you shouldn't put too much stock in the exact numbers, but the trend is clear. Readers will understand if you write:
I would say that it should be "buy in to".
A very similar question was asked in "Log into/login to/log in to", which I believe applies nicely here as well. And in that answer, another question/answer was referenced ( "into vs. in to") which also seems very relevant.