"It's very rare that publications double their frequency"

This quote by James Daly recommends that it is unusual for publications to increase their frequency. This might suggest that publications are rarely published more than once a month, or that publications are not often published more than when a week. It might also mean that publications are not often released more than once a day. This might be due to a variety of factors, such as the cost of producing more frequent publications, the problem of finding adequate material to fill the publication, or the difficulty of discovering adequate readers to sustain the publication. It might likewise be because of the reality that publications might not be able to keep up with the need for more regular publications. Whatever the reason, it is clear that James Daly thinks that it is rare for publications to double their frequency.