One reason people "don't have enough time" is they will squander a huge chunk of it on a minor task because there's nothing urgent going on. For example, they'll stretch a 10 minute call to an hour or try to do a nonessential task perfectly. This precludes them from accomplishing other tasks.

The cure for this is to set up blocks of time. If you do an online search for "time management" and then search inside the results for "Mark Lamendola," you'll find a few articles written by researchers quoting me on this. The concept is explained in those articles.

Here's a bit more explanation about why you shouldn't keep working on a task until you've done it perfectly. It doesn't matter. That's why. Many people will say, "But I have such high standards." What they are really saying is they have low standards. When you are so afraid of your own incompetence that you keep going over something looking for errors, what happens? You get far less done. An example will illustrate.

Let's say your job is to install electrical receptacles in homes being built. If you install them per convention, you can easily keep up with the builders and everyone is happy. The receptacles are a tad crooked (up to 5 degrees off plumb), vary in height from the floor by 1/16th of an inch, and have other variations. For example, the amount of wire  coming out of the cable to feed each receptacle varies between 6 inches and 9 inches. In short, they are not perfect. But, you put these in very fast--about 4 per hour. They are "good enough."

Suppose Gary comes along and says you do shoddy work. Gary gets out a laser device and precisely installs each receptacle within 0.005 degrees of plumb, mounts them within 0.001 inches of each other, and provides 6.125 inches of wire inside each one. Gary can install one of these suckers about every  3 hours.

Will a homeowner even notice the difference? Is there any functional difference? No to both questions. Is Gary doing a better job? No. Gary is doing a far worse job, because one quality factor is time itself. That really matters to the contractor building the homes. With Gary's "perfect" installation ("good enough" isn't good enough for him), the contractor can't complete the houses efficiently.

To do a job right, first define the purpose of the job. Then, define the quality criteria that serve that purpose. Going beyond that isn't delivering more--it's delivering less.