I think this is one of these questions where there is no right answer. You of course need a balance.
However, I suppose coming from a marketer it will be no surprise that I think getting your marketing right is crucial. I have been called in to companies so many times to get involved in projects where loads of cash has been spent on the product with no marketing having been contemplated.
I hope that the tech model of burning VC’s cash on the premise that ‘if we build a better mousetrap’ have gone as surely a model centred on customers and their needs and expectations has to make sense. Good marketing generates sales, which generates margin, which allows you to employ more or better people.