Honestly, it doesn’t make much business sense from the affiliate side. All of us on this forum are very motivated to succeed, so that sort of term doesn’t do anything positive in my mind.
Take for example an affiliate that works very hard to send a ton of traffic your way for a few months, only to see that conversions are rather low. This affiliate has made several conversions with you, but for business reasons needs to spend their time marketing a more profitable program and stops sending traffic your way. Apparently this means that your program will not honor the traffic sent previously since the affiliate has stopped sending you traffic.
Most programs work on a revenue share for the life of any real money signup sent your way since the person that signed up with your site may never have found you in the first place if it weren’t for the affiliate.