Dance together, but don't get Tango'd
> Array lifespans of four to five years seems to be the minimum
The key thing about storage is to not buy too much. That's where a partnership can be helpful.
Few companies will have small or zero growth requirements. They will know that their organic data growth will be X% per year. They will also know that the price of storage is ever-decreasing. That both gives them leverage and puts them in a spot.
On the one hand, it permits a buyer to dangle the carrot of long-term sales in front of a storage vendor: knowing that they will need a certain number of TB every year can be as attention-focussing as having their nuts in your fist. However being beholden to a single supplier for upgrades over a 2, 3 or 4 year term can lead them to (mistakenly) think it's they who have you by the short'n'curlies. And extricating yourself from what seemed like a good deal, when it all goes sour, can be an expensive and career damaging chore.
There is also a danger from dealing with the "Upstarts": those storage outfits who have been going a few years, but haven't joined the hallowed ranks of the "established" vendors. Apart from the obvious: them feeling the heat if the market turns nasty, there is also a big question of how they will support customers who are not in their mainstream marketing area. Will a U.S. based Upstart be ready, willing and able to provide excellent service to an EMEA-based organistion: or will you find yourself subcontracted out to the lowest, local, bidder? And at the back of the queue where feature requests and bug-fixes are concerned? There's also a consideration that a lot of Upstart's "growth" strategy can be summed up as: race for growth and sell out at the top. In which case you find your storage strategy has quickly become a dead-end business for one of the major players - who only bought the Upstart to get their customer base, or their tech. You will have gone from being a profitable fish in a smallish pond to being an annoying sideline in a sea of enterprise players.