IMO sales and marketing expenses should be minimal—essentially limited to testing different channels to see if they work. I'm sure this depends on the business

IMO sales and marketing expenses should be minimal—essentially limited to testing different channels to see if they work. I'm sure this depends on the business but I'd say if you need a lot of marketing spend in order to experiment it's a sign that you may not be enough of an expert on where to find your customers and you either need to find a way to gain that expertise or pivot to an area where you already have it.