Of course, it’s possible to earn money or make the sale with only one of the other two. You don’t necessarily need belief and value.
Consider the option where you have belief in what you do but others don’t value it. It doesn’t create any significance for them.
For example, you could go and rob and bank, sell a stolen car, peddle an insurance scam or undertake some other equally unethical pursuit. None of these activities are things that (most) people would see as valuable; but so long as you believe in what you do, it is possible – in the short-term at least – to earn a living.
Consider the other option, where you don’t have belief in what you do, but others see the value you bring and so as a result, you create significance for them.
For example, you may be good at your job and serve customers well. You’re diligent and particular and your customers enjoy working with you. However, you may not enjoy what you do or have any belief in it; but so long as your customers see that value then again – in the short-term at least – there’s the opportunity to earn a loving.
Whilst the first is far less likely, the second is more prevalent. It can be easy to just earn a living because others value what you do without personally believing in it.
The problem in both scenarios is that the story doesn’t end well. Incarceration looms – physically in the former, and mentally in the latter.
But people are attracted to congruence and alignment.
Therefore if you believe in what you do and create value for others, then the money, the transaction or the sale, follows as a consequence.