What do you consider when setting a deadline?

What do you consider when setting a deadline?

When I first started out on SEOClerks, I had very short deadlines and they were easy to meet as I had very little work. So for instance, if my deadline was three days and I only had one sale, then it was easy to get done with what I needed as there was just one project to work on. Very quickly, I started getting more sales and it was difficult to meet a three day deadline as I had ten projects to work on every day. So, over time, I found it to be a better strategy to have a longer deadline. The longer deadline might be a negative selling point for some buyers, however it helps me to be able to work on more than one project. And, since my work involves writing, it takes more time than some other types of services. I would rather have a longer deadline and be able to service more customers and do a high quality job, than a short deadline where I have to rush and sacrifice by turning in less than stellar work. For me, the longer deadline is working out as many of my SEOClerks and freelance customers want the work spread out over a month and not a rush job in one or two days.

What are some of the things you consider when setting a deadline? And, do you have long or short deadlines?