The length of an instruction decides whether it gets followed
Record yourself asking a five-year-old to put on shoes. Almost nobody says "shoes on, please." What comes out is closer to: "Can you get your shoes on, we're already late and I asked you twice, and don't start with the socks again."
That is one instruction wrapped in three complaints. The child has to find the instruction inside it. Frequently they do not, and what the adult reads as defiance is a parsing failure.
Working memory is the bottleneck
A young child holds fewer items in mind at once than an adult does, and holds them for less time. Every extra clause in a sentence competes for that space. By the time a request ends in reproach, the actionable part has usually been pushed out.
This is why the same child who cannot follow "go upstairs, brush your teeth, and bring down your reading folder" follows each of those three perfectly when they arrive one at a time.
A child who does one of three things has not ignored you twice. They have completed the instruction they still had.
Frontload the verb
Instructions that begin with the action survive better than instructions that build up to it. "Shoes on" lands. "When you're ready, and I mean now, I need you to think about shoes" does not, because the verb arrives last and everything before it is noise the child has to hold.
The same applies to negation. "Don't run" requires the child to picture running and then suppress it. "Walking feet" names what you want. Children act on the image they are handed.
Silence is part of the instruction
Adults tend to repeat the request while the child is still processing the first version. Each repetition resets the parsing. Three to five seconds of quiet after speaking does more for compliance than any rephrasing, and it is the hardest part to do, because the silence feels like being ignored.
What to try this week
Pick the transition that goes worst — usually leaving the house or leaving a screen. Cut your usual sentence down to four words or fewer, lead with the verb, then stop talking and count to five. Do it for five days before judging it.
Most people find the instruction is followed at roughly the same rate, but the argument that used to follow it does not happen. That is the change worth keeping.