Terrible delivery process

Extremely unsatisfied with the inconsideration of their delivery process. Why can't we consumers be told specifically around what hour delivery will take place? e.g we will be delivering between the hours of 3-4 pm rather than let us wait all day just to reschedule and then we have to sit tight again for another day regardless of our own personal and professional deliverables! This is so inconsiderate and it wastes time!