Everything is easy when you know how!
Sometimes students who have been struggling to "grasp a maths concept" suddenly say with a laugh, "Oh that's actually quite easy". I always reply "Everything is easy when you know how". It turns out I say it so often it has become The Maths Room motto.
Term one witnessed a lot of satisfying "Ahh now I get it", and "Ahh, now I see" and often it was just a gap in knowledge that prevented the full concept being understood. Once that gap was filled, the concept could be learnt, explored and applied.