My question is based on the following assumptions:
I think that children learn by their success, if a certain behavior "works" to get what they want or not.
In consequence: A child should never succeed getting something e. g. by screaming or a tantrum, as it otherwise has learned: "If I'm screaming (or misbehaving) long enough, I'll finally get what I wanted."
The problem: Often the child does not want to do what it is supposed to, maybe as it wants the freedom to decide itself what do to at what time.
This is not possible however, if there is not enough time to wait, e. g. in the morning if we have to go to nursery school to be there on time.
Our son (3.5 years) does not want to brush his teeth and we only have some minutes left until we have to leave.
In the evening I just leave him alone in the bathroom and say "call me if you are ready" and some minutes later he calls me on his own to brush his teeth.
In the morning there is not enough time and if I am afraid if we just leave without brushing his teeth, he will learn that he just has to do everything slowly to avoid this unpleasing "duty".
A similar problem is getting ready on time: If I tell him, to put his clothes/shoes on... and he does not do it, what measures are there to motivate him to do it in time?
So how could I motivate him to support me without using force?