Have 2 hours to do a 5 minute task?

Impossible effort of will.

5 minutes to do a 6 minute task?

Let's go!

When you're time constrained, there's no way to delay the start of it, you just have to go.

Having more time can make you less productive, "I can delay that by a few more minutes, just one more YouTube video…"

One good way to keep the time urgency up: spend a lot of time in your creative / flow state, so you have only a small amount of time to do the various annoying simple chores.

The momentum from the creative work, and the small amount of time available for the annoying tasks, helps you get them done lickety split.