Product market fit for scientific instrumentation
Most likely, startups start with a single product. The success of that product is, therefore, the only parameter that can be used to judge whether a new company has any future. Generally speaking, there is this idea of product/market fit to define when a company has developed the product the market they are targetting actually wants (or needs).
It is hard to tell when this fit happens. A useful metric is 'traction', defined either as number of sales, demonstrated interest, engagements. Once there is product-market fit, sales will follow.
This, however, does not necessarily adapt well for scientific-based instruments, in which the product development cycle is very long (thus hindering the possibilities of quick pivots before running out of cash), and the sales cycle is slow. After all, there's a chance instruments are expensive and therefore require demonstrations, visits, perhaps a customer asking for a subsidy to purchase equipment, etc.
One of the stages to understand whether product/market fit has been achieved is when customers talk about your product. For scientists this is very well defined: conferences and papers. Papers take time both to write and then to publish.
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