Spaces was developed as a organizational tool for teams. It has elements of Google Keep, Classroom, and Drive rolled into one. Given the greater popularity of these three tools, it's not surprising that Spaces never gathered momentum.
I suspect that the end of Spaces is also due in part to the pending launch of Team Drive (read my review here).
I don't expect many tears to be shed for Spaces. We can, however, observe a few interesting trends from the development and now end of this collaborative team tool:
1. Google likes internal competition.It's not uncommon for Google to launch competing projects and wait to see what sticks. Even when a project is cancelled, we frequently see the best features from that product rolled into an existing tool (i.e. Wave being absorbed by Google Drive).
2. Google's pace of innovation has increasedGoogle has been on a tear over the last 18 months in terms of launching new products (Spaces, Trips, Allo, Duo, Home, Pixel phone, Daydream...) and discontinue unpopular products (Spaces, Research tool, hangout apps). When engineering talent is at a premium, you have to pick and chose your projects.
3. Google is focused on teamsOver the past year Google has focused a lot on helping teams work more efficiently. They have added improved search through machine learning, launched Team Drive and cloud search (coming soon).
What do you think? Will you miss Spaces? Are there any missing pieces to Google's collection of collaborative team tools?