Are the creators submitting able to make a clear judgement of the average return and their own individual chances from these contests?
It is not that hard. You can make a rough guess of the number of people that are interested (especially if they've done contests before, or have people replying to the announcement). This doesn't have to be that good, as in just an order of magnitude is probably more than accurate enough. If the sole motivation of creating art for you is monetary, and you are risk averse, then you round or bump up the estimated response with an appropriate safety factor. Others that are more risk-neutral or risk-loving can round down. Yet others with different motivations that would enjoy doing so with little to no payout could end up ignoring it completely.
If you are so risk averse that making wide safety margin assumptions, like say 10 times as many people enter as is watching their announcement, is not enough of a guarantee, then trying to make money from art really is not the right business for you, as you won't be able to make satisfactory judgement of the risks involved in even simple commissions.
It is not that hard. You can make a rough guess of the number of people that are interested (especially if they've done contests before, or have people replying to the announcement). This doesn't have to be that good, as in just an order of magnitude is probably more than accurate enough. If the sole motivation of creating art for you is monetary, and you are risk averse, then you round or bump up the estimated response with an appropriate safety factor. Others that are more risk-neutral or risk-loving can round down. Yet others with different motivations that would enjoy doing so with little to no payout could end up ignoring it completely.
If you are so risk averse that making wide safety margin assumptions, like say 10 times as many people enter as is watching their announcement, is not enough of a guarantee, then trying to make money from art really is not the right business for you, as you won't be able to make satisfactory judgement of the risks involved in even simple commissions.