Sound design happens without effects and sounds/sequences are rendered. Then, arranged and effects added on tracks. Usually little processing on buses, maybe a bit of EQ, maybe TG12345 on drums. Pre-Master usually has the "beautification" plugins, EQ, compression, Gullfoss. Master is loudness only (clipping/Inflator, high-passing, limiter) and recently an EQ for the headphones (off when rendering).
tl;dr buses use less plugins