The growth of tablets has been held up as one of the big, disruptive forces in personal computing, with the more portable, touchscreen devices eating into sales of laptops and other, larger PCs. But a report out today from IDC puts a little dampener on that line of thinking: the analysts there say that they are revising down their forecasts for 2014 tablet shipments (and subsequent sales), as people hold on to older models for longer, and ever-larger phones continue to muscle in on tablet territory.

IDC says it now believes that 2014 worldwide tablet shipments will reach 245.4 million units, compared to previous projections of 260.9 million units. “The new forecast represents a 12.1% year-over-year growth rate, which is notably lower than the 51.8% year-over-year growth of 2013,” its analysts note, a robust 2013 figure echoed yesterday by one of the doyennes of Internet analysis, Mary Meeker.

As a point of contrast, IDC noted earlier that smartphone shipments in 2014 will grow to 1.4 billion units, a rise of 23% over 2013, with Android continuing to dominate at an 80%+ market share.

IDC’s downward revisions, it should be noted, are not being made in a bubble. The company, you could say, saw the writing on the wall before 2014 even started. Back in December, the company lowered forecasts for the next four years in light of the popularity of those big phones — aka “phablets.” It believes that by 2017, tablet growth will slow to a single-digit crawl.

Investment banks Morgan Stanley and Goldman Sachs also recently spelled out their more pessimistic views recently. Morgan Stanley, which like IDC puts growth at 12%, put the blame on lack of innovation. Goldman, meanwhile, believes growth will be at 15.4% after a “disappointing” Q1 of sales.

IDC’s VP Tom Mainelli believes that the premium prices put on bigger devices by the likes of Apple and Samsung have had the effect of encouraging users to hold on to devices for longer. “Consumers are keeping their tablets, especially higher-cost models from major vendors, far longer than originally anticipated. And when they do buy a new one they are often passing their existing tablet off to another member of the family,” he writes. Indeed, when you consider that tablet purchasing follows patterns closer to PCs rather than subsidised handsets, it seems natural to consider longer replacement cycles.

And in that vein, the devices that are being sold via carriers are continuing to get bigger. “The rise of phablets – smartphones with 5.5-inch and larger screens – are causing many people to second-guess tablet purchases as the larger screens on these phones are often adequate for tasks once reserved for tablets,” he writes.

On that front, IDC says phablet shipments have more than doubled in the last year as a share of smartphones, accounting for 10.5% of them in Q1, or 30.1 million units. Rather than drive more production of interesting small-screened models, IDC thinks that this will result in tablets getting bigger to further differentiate themselves.

This is interesting in light of what the current tablet market leader, Apple, may end up doing with the iPad — perhaps we may really see larger-screened versions coming online this year as the hardware rejoinder to Eddy Cue’s promise that this year will see the most exciting line up of products that we have in a while.