Makers of hard disk drives have been revealing one advancement after another, but they might not be able to keep it up for long. Seagate thinks so at least.  In the past few years, as has become fairly customary on the IT industry as a whole, new breakthroughs have been reached in HDD research and development.

One might say that HDD makers actually had to move faster here, since SSDs are breathing down their neck (or not, depending on one's view). At any rate, HDDs came a long way in a fairly short time, as has their usage, but here lies a hidden problem.

In 2011, the demand for HDD storage was of around 400 exabytes, where one exabyte is a million terabytes. 2012 will see the need for an even higher number, but this doesn't mean that the average capacity will rise.

Seagate says that, with the zettabyte level closing in (2015-2016), the cloud and other businesses will take up most of the sales.

In other words, more drives are needed, but this leads to component supply insufficiency. A single HDD has over 200 parts. More drives mean more heads, ramps and other components, and with the cloud siphoning the majority, client HDDs will have to make do with less.

Long story short, capacity growth for HDDs will not rise all that fast over the next decade, although HAMR (heat-assisted magnetic recording) will come to the rescue in 2016-2017.

"It probably plays out that on the client you start by going to more a single disk solution. [...] So you probably start seeing a reduction in heads and disks for clients, but then you start seeing an increase for cloud," said Steven Luczo in an interview with Forbes.

"When you look out at 2016-2017, then you have a next generation technology called HAMR