I fully understand the overall 10,000 song limit for offline use in Spotify across up to 3 devices, but I don't see why the limit must be divided amongst 3. It may seem like your providing a convenience for people with multiple devices, but it actually does the contrast. I would rather the 10,000 song limit not be divided to 3,333 for three devices, and instead have an overall 10,000 offline song limit for the entire account. This would make it much easier for people, such as myself, who only use one device.
Update (by Marco):
The discussion about assigning all 9,999 tracks to one device will continue here:
https://community.spotify.com/t5/Live-Ideas/All-Platforms-Playlists-Allow-all-9999-tracks-to-be-assi...
Update: This has been re-posted here.
Although I appreciate the sentiment, we can't change this in the near future. Case closed for now.