One of the main points of the project was for security reasons. Updates to the Chrome browser build for ChromeOS came out later than the standard Linux/Windows

One of the main points of the project was for security reasons. Updates to the Chrome browser build for ChromeOS came out later than the standard Linux/Windows/Mac Chrome builds because the special chromeos build needed time to be integrated/tested with the rest of ChromeOS. With LaCros, the browser can be updated independently from the rest of the OS.