MORE...? The 'positives' to promote when selling include the upside:
more profit, more sales, more time, more leisure, more pleasure...
LESS...? The 'negatives' to promote when selling include the improved 'other side':
less cost, less overhead, less worry, less stress...
Maybe... no-one believes that you can get them more of the mores? (or maybe you are trying to sell the wrong mores [profit/sales/cash in the B2B environment... time/pleasure/happiness in the B2C environment]?)
Maybe... less is a more believable offering?
Maybe you just can't make sweeping generalisations!!!
As long as your cost/fee/price is
- less than the overall positive/gain/profit, or
- less than the cost of the overall saving
then who cares!?
So, getting back to basics...
Explicitly what is the benefit of your product/service?
Have you got the proof?
Can you demonstrate (beyond a shadow of a doubt) that your product/service will deliver?