Avoiding companies where the % of revenues spent on staff and...

Avoiding companies where the % of revenues spent on staff and opex is this high would have saved one from investing in companies such as:
Amazon
For those with short memories, Amazon went public in 1997 at a market cap of $438 million (equivalent to $6 per share). The prior year's gross revenues were $16 million, net revenues were $3.5 million (comparable to ARR)....Operating expenses were $9.4 million for a net loss of $5.8 milion and the company had $6.2 million of cash. To use Kingz terminology, "staff and operating expenses had been skyrocketing" increasing by a factor of 20x over the prior year such that cash burn and op losses had increased from $300,000 a quarter to nearly $2.5 million a quarter .....But cash burn had plateaued and started to decline.
If you had invested $25,000 in the Amazon IPO, it would be worth $7,445, 833 today.
Workforce
Slack
etc etc.

LVT's staff costs in June were approximately the same as they were in June 2018 despite the company growing by 260%
LVT's staff costs in September will be approximately the same as they were in September 2019.

It is hard to conclude that staff costs are "skyrocketing"

Instead we should be pressing the company to explain increased R&D spend......what is the product pipeline?
What is the mix between annual subscription and monthly/quarterly subscriptions? Is this mix changing?
What % of recent customer wins by value have been stand alone products (LiveTile Design) and what % have been bundled sales?
What is the current value of the pipeline? What has been the historic win rate on the pipeline? Has the win rate been changing?
How do you see the direction of cost of customer acquisition? Is it declining or increasing?

These are the real drivers of value.

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