"It means your legacy is assured, as well as your own sense of self-worth," he says.
"You leave with relationships in good order, and you have not outstayed your welcome."
He says many high achievers are loath to lower their standards. If they feel they might not continue to operate at their best, leaving the role might seem the best decision. Additionally, if someone has achieved all they want in a role they may feel it's time for a fresh challenge.
Patterson says there a a number of signs that a person is tiring of their role; reduced enthusiasm is one of the first.
"This can then be accompanied by an increase in stress because there is a feeling within the person that the job isn't being done as well as it could. High achievers don't like that," he says.
"If the job feels too much and stress elements are beginning to creep in, but the genuine motivation to conquer the difficulties is gone, then it is probably time to move on."
There are a number of practical considerations that influence the decision around whether to stay or go.
"These can include the financial impact of the decision, stage of life, emotional attachment to the role and organisation, opinions of spouses or partners, and health factors," he explains.
"Whatever the logic of the situation, for it to work for the individual going forward, the decision absolutely has to feel right for them."
Once the decision to leave has been made, this needs to be communicated clearly to key parties in the workplace.
"It's important to work out a departure and hand-over that has the least disruption, and ideally allows the organisation time to appoint a replacement. Going out in a blaze -- no matter how tempting -- or in a selfish and inconsiderate way, are never clever things to do," he says.
Patterson continues that it's good to be judicious about who you speak to before deciding to leave.
"Key considerations when working out who to speak to are the relationships the person has with decision makers in the business, and the sensitivity of the role."
John Key-type grand announcements have a lot of impact; one-off big announcements are also probably the best way to declare your decision to resign.
"The drip-feed approach encourages speculation and can also result in the person being marginalised before they have finished the work," says Patterson.
"The reality is that when a person announces they are leaving, people's minds dial forward immediately and look to the future."
Much has been made of Key anointing of Bill English for New Zealand's top job. Patterson says that is good practice for leaders to pass on recommendations for a replacement, but sometimes directly filling the existing role isn't the best option.
"As circumstances vary from situation to situation, often a direct replacement is not the answer. Frequently roles are resized and reshaped and essentially become new roles and that is where a pool of talent can be considered," he says.
He says that although there are benefits to leaving a role when you are on top, there are also downsides.
"Leaving while on top of your game means you can't ride the wave of success to push through other projects," he says.
It's often best to have a new challenge in place before you say goodbye to your current role.
"The preferable situation is that one leaves one role because what is on offer outside in terms of actual or potential opportunities is more attractive than the current situation. This gives a person 'go forward' and immediately creates momentum and excitement."