This is caused by the "Auto-learn routes to frequent destinations" (In Settings, Advanced). And it's not a new thing - it was in the previous version of the client.
It's very misleading. It learns destinations
that you normally travel to from particular starting points. So if you use Waze for your daily commute, it will soon learn that you normally go to work from home and vice versa. Every time you leave home it will offer to route to work and every time you leave work it will offer to route to home.
Waze does not learn routes. Once you have accepted the destination, it then uses its normal routing algorithms to work out the best route - but the route provided is not based on any personal "learning", except to the extent that your travel along that route is just part of the mass of data that Waze has from all the users travelling in the area.
It's possible that Waze may learn more than just 2 "routes". I don't know because, like you, I found it more trouble than help and turned that setting off after it learned home<->work and work<->home.