Start your own company.
Eventually you'll want to know what users are doing, and specifically why they're not doing what you expected them to do after you spent ages crafting the perfect user journeys around your app. Then you'll start wondering if installing something to record sessions is actually a great idea that could really help you optimize things for people and get them more engaged (and spending more money.)
Fast forward three years, and you'll be looking at the source of a page wondering how things got so bad.
> Eventually you'll want to know what users are doing, and specifically why they're not doing what you expected them to do after you spent ages crafting the perfect user journeys around your app
That's putting the cart before the horse. The way it's properly done is just to invite a few users and measure and track their interaction with your software. And this way you'd have good feedback instead of frustrating your real users with slow software.
You forgot the best bit - not removing the ones you no longer use!