Hey there,why is it needed in C4D to convert objects? I'm from Maya and there's no need to convert objects first. Is there any feature in C4D why this is needed? Thx!- bb

yes there is...c4d treat the object has to option ...converted and unconverted....the unconverted make provit on simulation....you can manipulae simulation faster than using converted object...because unconverted object didnt store any heavy history data and can be reduce their segment. 
c4d just like 3dmax..if you want to modified it convert to polygon object or poly mesh...in c4d 12 there a feature deformer called correction deformer...it can modified unconverted primitive become polygon object directly without to convert the primitive it self