Every beat producer out there's searching for one thing, the perfect beat. Naturally, nobody wants to find the perfect beat just once, they'd like to find the formula for the ideal beat, making something vital, each time they start up their sequencing software.
Of course, what the perfect beat looks like changes over time. Like anything else in music, things don’t stand still for very long, if in any way. Hence the idea of looking for the perfect beat can be a search that goes on indefinitely, even if you find you've reached perfection, or neared it, from time to time.
But what makes the ideal beat loop. Is it invention? Is it the way a vocal fits over it? Is it the way that it subtly evolves or changes around a hook? Obviously all these things are crucial, if you're trying to find perfection. Any producer who wants to make the final beat will need to have these things, in order to maximize the probabilities of hitting perfection.
Clearly, there are techniques of making it much more likely that perfection is hit. For example, making certain that you are learning your software inside out, trying out any new ideas that come to you and paying attention to other music, both the classics and the new stuff that others are doing.
At the same time, you need to avoid copying others, maintain your mixing skills and get the most out of the artists you're employed with. Getting input from vocalists, for example, can make a positive impact on how your beats work, in truth, sitting on a track.
It is also pretty important to get the balance right, when it comes to self feedback. You do not need to be so imperative that it stops you trying new things; on the other hand, if you are not vital enough, it can be tough to reach a point of perfection. When you make beats it is chock-full of that sort of tightrope walking.
For more info on writing beats read about music creation software and sonic producer.