Because the convenience of SharePoint and O365 is a huge productivity boost compared to having everything self hosted on-prem. Or better yet, the other way arou

Because the convenience of SharePoint and O365 is a huge productivity boost compared to having everything self hosted on-prem. Or better yet, the other way around, having everything on-prem, outside the cloud, kneecaps your productivity. Case in point, I currently work in a relatively niche cybersecurity company, so naturally, most customer stuff is done and stored on-prem for security reasons since we handle a lot of customer sensitive data and storing it in anyone's cloud is a big no-go for any customer. By far the biggest issues are managing the on-prem environment and moving the data back and fourth between the O365 environment and the on-prem environment, as the O365 environment is actively used by the customers, C-suite, business, sales and upper management, while the on-prem environment is used by the engineers, lower and middle managers, which is the biggest PITA that I have ever dealt with. Nextcloud, Thunderbird, Libre Office, Element chat etc. are great but what Microsoft offers with the O365/sharepoint ecosystem is something else and copilot will move the goalposts even further. Also, I'm not aware of Microsoft having had any data leaks or breaches, so maybe they have gained enough trust in the corporate space that makes companies at ease storing all their stuff in Microsoft's cloud for the sake of convenience.