Duff said the Shopping Channel differed from other channels in that its primary focus was on selling products.
"The most important figure to us is the number of people coming back to the channel. We focus on buyer numbers rather than audience numbers."
If the channel was able to release figures based on frequency of viewings, the ratings number would increase considerably, he said.
"From our online purchasing traffic we have a high frequency of repeat buyers showing us that we have significant repeat viewers.
"These are not reflected in the unique views number."
The channel's own internal figures showed 15 per cent of those who purchased in October made another purchase in November, he said.
Customer numbers from October to November had increased by 25 per cent and December was on track for a 200 per cent increase on November.
"We are never going to be happy as one can always do better," Duff said.
"We are constantly reviewing what we are doing and looking at ways to improve."
Broadcasting on Sky channel 18 and Freeview 18, The Shopping Channel went live with a visit from Desperate Housewives star Eva Longoria to boost publicity.
A run of bad taste jokes drew attention to the show in its early days, with viewers complaining on Facebook about a "creepy" banana joke, "disgusting" food, and a lack of contact details showing up on screen.
The channel announced last month it would be cutting its number of weekly live filming days from six to two and doing more pre-recording.