There are, IMO, quite a lot of badly tagged questions and... not very good tags. Some of them were discussed on meta recently; some of these discussions show, IMO, that users who created these tags don't always understand tagging system of Math.SE well enough.
On Meta.SO one needs 500 rep to create a new tag, on SO — 1500 (!) rep. On Math.SE — just 300 rep.
Since its creation Math.SE has grown a lot. Maybe now it's time to (ask to) raise reputation requirements for creating new tag on Math.SE? (Say, to 1000 rep?)