Busy schedules=the big killer
In my experience, the worst enemy of regular Bible study is being overloaded in my commitments. There are two things that can be said about this. The first is that we make our schedules according to our own priorities. If we believe that it is important to eat and sleep, then we make time for them. If we really believe in the importance of reading the Bible, then it will have a high priority. So, when we have too much to do, and something must get squeezed out, it will not be the Bible.
Secondly there is the principle that if we honour God, then he will honour us. If we give the reading of his Word its rightful place, then we can look to him to help us cope with the rest of the day. But if we dont have time for him, we sometimes find that the Lord allows our situation to get even busier, and we have even less time.
It is helpful to set a regular time each day when we know we will not be interrupted. For some it is better in the morning, and others prefer the evening. This is something that we all have to work out for ourselves.