If a soldier leaves his post early without being relieved by the proper authority then everything that the soldier was responsible for at the assigned post is now left unattended. That means any equipment is left on display for anyone to take or use without being reprimanded and this could result in theft or botched inventory. Also this leaves the property subject to vandilization which could be very expensive to clean up. It is important to stay at the assigned post and only to retire from that post when properly relieved.
If a soldier is not at his post at the time he is assigned this means his post is left unattended and he is unable to carry out his duty to investigate unusual or suspicious occurrences on or near his post. If the soldier is unable to do this then there could be a threat undetected and damages could be done that may not be able to be undone. For example, someone could be in an unauthorized area but no one would be there to escort them away or stop them from tampering with anything that could be damaged beyond repair.
If a soldier leaves his post at a time he is not instructed to do so then he is unable to apprehend suspicious persons or all persons involved in disorder occurring on or near his post. This could be very bad because there could be a threatening person trying to cause harm to those around and no one would be there to stop them allowing them to carry out their actions and cause possible damage beyond repair.
Not only is it unacceptable to leave a post earlier than assigned it is also unacceptable to show up late to duty. This causes an inconvenience to the person said soldier is supposed to relieve. This may cause the person on duty to become irritable with having to stay late and become distracted with their disdain that they are unable to carry out their duties properly. This may also cause said person to be grumpy to innocent bystanders causing the army to have a bad look. In general the first general order is a set guideline to teach soldiers how to take charge of their duties and conduct them in a military manner. This order helps keep order and discipline among the Army.
Failure to follow duty can result in various punitive actions against service members. Also failure to follow duty can result in non repairable damages, putting others in harms way, or causing disorder among the company. It is always important to remember ones duty in this case being I will guard everything within the limits of my post and quit my post only when properly relieved. It is also important to remember ones responsibilities as I have stated above and will state again: the guard is responsible for anything that occurs within the limits of his post while he is on duty, including all equipment and property located within the limits of his post. A guard investigates immediately every unusual or suspicious occurrence on or near his post provided he does not have to leave his post to do so. A guard apprehends all suspicious persons and all persons involved in disorder occurring on or near his post provided he does not have to leave his post to do so. If not followed properly chaos could occur.