Following an explosive start, Samsung has lost US$12bn stock as Galaxy S4 sales look set "to disappoint."

Despite selling one every second since releasing the product in April, the South Korean company has seen shares fall 6.2% as demand for the device slows down.

Falling the most in over nine months, analysts JPMorgan Chase & Co cut its share-price estimate for Samsung by 9.5%, subsequently lowering its 2014 earnings predictions by 9%.

“Compared to S3, S4 had stronger momentum in the first quarter of launch,” the analysts reported.

“But the following quarter’s shipment is expected to be disappointing and its peak-quarter number seems way below our previous estimates.”

As a result, Samsung is now expected to shift 60 million this year, down 20 million from previous predictions.

The news is in stark contrast to reports two weeks ago, when Samsung confirmed channel sales of its smartphone has surpassed 10 million units sold in less than one month after its commercial debut.

“On behalf of Samsung, I would like to thank the millions of customers around the world who have chosen the Samsung Galaxy S4,” said JK Shin, CEO and President of the IT & Mobile Communications Division, Samsung last month.

Sales of the previous model, the Galaxy S3, reached the 10 million mark 50 days after its launch in 2012 however, while the Galaxy S2 took five months and the Galaxy S seven months to reach the same milestone.

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