Bundling. This is how tech juggernauts stop growing startups from reaching true scale. Let's examine the case of Slack vs Microsoft Teams.

Step 1 - Create a competing product. As Slack was growing & picking up steam, Microsoft launches Microsoft Teams with similar features.

Step 2 - Include it as part of a bundle. Microsoft has thousands of enterprise customers who purchase Microsoft products (Word, Excel, Outlook) as part of a bundle. One day, Microsoft Teams is part of a bundle at no additional cost. Instead of spending $$$ on Slack, companies decide to just use Teams because it's marginally free for them.

Step 3 - Increase the price of the bundle. Every couple of years Microsoft increases the price of the bundle and bakes in the prices of new tools. Customers have already integrated the tools and at this point switching makes no sense.

Ala! Microsoft stops a competitor from scaling to millions of users while grows its own revenue.