your assumptions and blanket statements about everyone doing things is just wrong. Its like someone who promises anything @ 100%... you know they aren't truthful, because nothing is 100%. How would you know what info the other guy gave you isn't a fools errand rather then useful info? Counterintelligence is a thing.
Lots of companies don't pay attention to their competitors aside from just passing glances. Sometimes your competitions action is not in any way visible to you, for instance when trying to win top secret gov design contracts. When you are on the bleeding edge or the only one working on something, there is just no need. I could come up with a lot of reasons why spying is useless(not saying it doesn't have a use, just not useful in every case as you propose)... but i guess i am confident in things, rather than paranoid. Worrying about what someone else is doing is just wasting time, unless they are coming for you.
My comment is not an assumption or a blanket statement, it's the simple reality.
There is never a single company working on the bleeding edge. Those who are take a lot of precautions to keep their secrets and are keen to learn their competitors' secrets.
If you work on the cutting edge in tech just send your CV to your company's main competitor. They'll be quick to invite you for interview... To buy your competitor's product to take it apart and study it is also a time-honoured classic. These are just basic examples.
