If it’s just hours, that’s fine. I’ve spent months on a system before that ultimately got scrapped. When I was at Google, they accidentally had two teams working on basically the same project. The other team, with about 40 engineers, having worked on it for about a year, had their project scrapped. My team was meant to do the same work, with about 23 engineers. So if you’re ever wondering why Hangouts Chat launched kinda half baked, that’s why.