Wordplay

This is a pun to me. In italian language "Piano" has a lot of meanings: project, flat, floor, plane, gently, carefully, etc. In this case, the meaning I want to give it is: "slowly". The red and white round is a road sign meaning: "do not drive over 50 Km/h (31 miles/h)". Now, from my POV, driving at 50 Km/h is really slow.