Some very strong arguments have been made for why BeOS would have been a better choice for Apple at the time, but the truth is that Be was always a second choice for Apple if NeXT could not be acquired.
Apple got a great two for one deal by acquiring both a solid UNIX-based foundation for their future and Steve Jobs, but Jobs was really the crown jewel. Apple was in a terrible position at the time, and most industry watchers didn't expect them to survive.
WIRED ran their famous "101 Ways to Save Apple" cover story around that time, and Michael Dell made his infamous quote that Apple should "shut down and give the money back to the shareholders."
It really was a bleak time, and a technology solution was only part of what Apple needed. Steve Jobs' return was what the acquisition was ultimately about.
2017: Who's Michael Dell?
Steve Jobs is better known dead than Michael Dell is alive.
> It turned out that Michael Dell wasn't perfect at predicting the future. Based on today's stock market close, Apple is worth more than Dell. Stocks go up and down, and things may be different tomorrow, but I thought it was worth a moment of reflection today.
He's a guy worth $23.5B (says Google today).
Dell may not be very exciting, but Michael Dell is doing fine.
In a bizarre turn of events, he took Dell (the company) off the stock market himself making it non-publicly owned.
Even Acer (remember them) is worth almost 3x what Dell is today.
At that time in 1996 they knew that Microsoft was going to take the NT kernel and build it into something very stable and more consumer friendly. NT 3.5 and NT4.0 never saw widespread consumer adoption, only in corporate environments. But the later release of Windows 2000 was significantly more stable and capable than legacy MacOS.
https://www.google.com/search?q=dec+alpha+windows+nt&ie=utf-...
EDIT: Actually he HAD the opportunity and because he passed it up we have Mac OS X today!!
From Wikipedia:
In 1996, Apple Computer decided to abandon Copland, the project to rewrite and modernize the Macintosh operating system. BeOS had many of the features Apple sought, and around Christmas time they offered to buy Be for $120 million, later raising their bid to $200 million. However, despite estimates of Be's total worth at approximately $80 million,[citation needed] Gassée held out for $275 million, and Apple balked. In a surprise move, Apple went on to purchase NeXT, the company their former co-founder Steve Jobs had earlier left Apple to found, for $429 million, with the high price justified by Apple getting Jobs and his NeXT engineers in tow. NeXTSTEP was used as the basis for their new operating system, Mac OS X.