how many times do you automate one item?

well, on my recent playthrough im trying to centralise items that we get from etiher refineries or constructors, so i have factories of plastic rubber silica steel pipe etc. my reasoning is to do it once and for all for every item.. As an idea i like it.. but on practice it makes some factories either small or not as exciting as an electronics factory..but on the other hand. automating the same stuff again and again in some other factory also feels a bit boring.. and i did every (inventory worthy) item already on my main base, but now i want to or have to automate even turbo motors again for the final project..do you guys do it like me? or do you get through til the last tier with hand bringing to containers for manufacturers etc. ? how do you plan your whole playthrough?