Modern parents often feel responsible for keeping children continuously entertained. The opposite is more developmentally useful — bored children learn to entertain themselves, which is the foundation of creativity, self-direction, and emotional regulation. The boredom is the work, not the failure.
What over-entertainment costs
Kids don't develop self-direction. Parents become exhausted from being entertainment directors. Activity dependence — kids need external stimulation to be okay. Less imaginative play. Less time outdoors and unstructured.
What unstructured time produces
Imaginative play (most rich when self-initiated, not adult-led). Boredom-driven creativity. Sibling collaboration. Comfort with own company. These are developmental skills built through doing, not through being taught.
Aim for at least 60 minutes daily of genuinely unstructured time. Kids may complain initially; the second week, they're building forts. Skill develops by week 3-4.