As a company we often get asked to take on commission only projects. Our answer to this is always no, for three reasons. Firstly, it's not our responsibility to take risk on for other companies, secondly, it doesn't show a lot of faith in us that the client wouldn't be willing to take the risk of paying us and thirdly (and by far the most important point) it shows little faith in their own product/service.
The largest determining factor in the success of a sales campaign is of course, the offering it's self. That being, the market's requirement for your product/service multiplied by the value perception.
In most cases people looking for 'commission only' sales people have a weaker offering or they would not be desperate for someone to take risk on to sell it. IT WOULD BE SELLING WELL ALREADY!
I don't mind people asking us as an outsourcing company, I can understand why they do, what really gets my goat up is when I see commission only sales jobs being advertised.
There are exceptions to what I'm about to say of course (commission based structures such as sale/return products to your supply chain and for part-time MLM businesses is relevant and in fact progressive) but most commission only sales set ups I have come across have been doomed to failure. It's hugely unfair to expect someone to come into your company and work full time without the guarantee of at least a basic salary at the end of the month. People tend not to last long in these roles.
There also tends to be less support for the sales people and less structure (i.e. sales process) to work to. It's a sink or swim type approach. The companies employing such an approach tend to blame the unsuccessful people as being 'useless sales people' rather than consider what damage commission only is doing to their ability to generate customer relationships etc.
You don't pay your production staff per item they make, you don't pay your bookkeeper per excel line they fill in, why would you choose to outcast the people who represent you to the world??!
I find it ignorant at best and greedy at worst. Certainly isn't how I'd ever advise a client to structure their company! I'm all for performance related bonuses but if you're not willing to invest in your people, then it tends to follow that they don't invest much in your product/service for very long.
PS. The above is quite a damming view, I'm aware. There are exceptions to every rule. If you have a commission only structure that works really well for your company and your staff, I'd love to hear about it - drop me an email.