Please read this piece of manual: Defold project settings
Also, this post might be useful: Defold 1.4.3 BETA - #16 by AGulev
Long story short: all the components and GOs, under the hood are reused by the engine. Let’s name it pools for simplicity. So you don’t create/remove objects, you just increase/decrease the count of components currently used. To make it more efficient all the pools are
allocated in advance, which helps to keep Data Locality which needs for cache coherence.