There are three pitfalls of “I’ll do it later”.
The first one in that “later” rarely comes. When we are in the present and we say “I’ll do it later”, we expect a future moment in which we will not only recall that we have that thing to do, but we will also be sufficiently free, awake, willing, energetic to actually do it. As our lives go by, we very rarely get to those moments, various different things getting in the way.
The second one is that as we postpone things, we end up increasing the clutter. Mental and material clutter alike. Keeping things in mind drains energy, and we can only remember a limited amount of things at any given moment. We then use to-do lists, productivity apps, calendars, email inboxes, reminders. And when we defer an item, we end up making it more and more difficult to see and act upon it. It’s what happens when your inbox unread list grows above ten emails.
The third one is that the thing we were supposed to “do later” will certainly pop up in a moment when we can’t do anything about it. Say, when we are already in bed, or while we are driving to work, or when we have just started playing with our kids. And we will feel a little more miserable, and probably end up doubling down on the “I’ll do it later”, resetting to number one of this list.
It turns out, many of the things we push to “later” can actually be done now, without to much of a distraction or effort. And if there are too many of those, than it is probably time to rethink priorities and what is important. Keeping many balls in the air will eventually make you drop all of them.