Because there's no other choice for entry/mid-level positions (and some lower end senior ones). Thankfully they are not 5 hours long, that's something I would also avoid.
For instance, in my recent job search for a new grad role, I had to do an OA for every company but Jane Street and Databricks (props to them).
For instance, in my recent job search for a new grad role, I had to do an OA for every company but Jane Street and Databricks (props to them).