Codeacademy doesn't overwhelm beginners with information. It gives bite-sized information, the bare minimum needed to finish a task and get to the next one. As the course progresses, it slowly fills in background information.
If you run an infinite loop, the browser freezes. Many other similar websites will give you an error, preventing the loop from running. Though not a bug, the lack of feature to stop infinite loops from running can be quite frustrating to beginners.