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"They Did It Yesterday"... So Why Can't They Today?"

  • Jun Lim
  • Jul 23
  • 2 min read

We often notice changes in behaviours and think, "they did it before", "why can't they do it again?" Most people unintentionally confuse ABILITY (i.e., do we have the skill to do something) with CAPACITY (i.e., do we have the resources to use those skills).


Ability answers our question of "Can they do it".

Capacity answers our question of "Can they do it in this moment, under these circumstances".

Ability is more stable and changes over time... but capacity is more fluid and changes throughout the day.


We may have the ability... but not have the capacity.


Capacity is like a phone battery. Every task uses some battery—but the amount each task uses isn't always the same. Getting dressed might use 2% one day and 10% another.

Even when we're not actively using our phone, background apps are still using power.


Our "background apps" might include:

  • poor sleep

  • sensory overload

  • worrying about something

  • illness

  • changes in routine

  • concentrating harder than usual


Depending on the background apps running, by the time we open the app we need, there is less battery available.

The task stays the same, but the available battery changes.


Imagine a child who independently puts away their lunchboxes most evenings.

But today, "they refused".

Reflecting on their day, they may be/ have:

  • Recovering from yesterday's birthday party

  • Assembly

  • Worrying about who to play with

  • Shopping after school

Same child, Very different available capacity.


Let's start asking:

  • "Are we expecting the same capacity as yesterday's"

  • "What's different today?"

  • "What might be making this harder?"

  • "What's their battery level?"


The goal isn't to push through until we need to recover. It's to recognise when our capacity is changing, and make small adjustments that help life remain sustainable..



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