This is related with How to work with "Warning icons" in Planning Worksheet
Here, we have an scenario where NAV does not respect order modifiers (maximum/multiple/minimum order quantity) when there are exceptions. As we mentioned in earlier post, exceptions are ... exceptions!!! Yeah, I know you might have an issue but, isn't this a situation that should occur exceptionally in your customer? If for whatever reason, these are not exceptions, you might have an issue with your planning parameters. When NAV flags the Warning Icon, it means there are exceptional situations like negative inventory, stock below safety stock, ...
The issue here is that customers treat all these scenarios differently. If we have the inventory level below safety stock, one customer might wait for the next planned replenishment to increase the ordered quantity. Other customers might create an urgent replenishment for the required quantity regardless of order modifiers since safety stock should not be rounded with order modifiers (it increases safety level in fact) ... Or ... whatever. Exceptions are treated differently. We mentioned this on that previous blog. What we also mentioned is that NAV design does not activate the "Accept Action Message" flag when this is an exception. What this means is that NAV is not suggesting a replenishment. It just warns the user of this exceptional situation for the user to take decission on how to address this. Thus, it should only be understood as NAV warning you that an exceptional situation exists.
And, that is why NAV does not respect order modifiers. It only warns the user about an exception situation (ie. inventory level is 20 pcs below safety stock). It does not suggest the user to replenish (ie. it does not suggest to replenish 20 pcs). Thus, user need to decide what is the best to address this exception ... and to consider order modifiers if required.
As stated, different customers treat exceptions differently. From a standard code, it is true we are not taking into consideration the order modifiers ... but this is an exception and should not occur but in very rare times. Thus, we need to manage customer in the fact that this should not happen to them frequently and that we are not suggesting anything ... we are only flaging the exceptional scenario for the user to decide action to take.
I understand the reasoning your are stating and think it makes fairly good sense. But i think i would be an improvement to NAV if it was possible to setup the way the system works. As you state customers to things differently but in my view it all comes down to whether or not we respect the order modifiers when we go below safety stop. And here it would be an improvement of NAV to have that choice as a setup parameter.
I completely disagree with not respecting order modifiers for "exceptions". In many cases, those modifiers represent the only way the product can be physically ordered. For example, someone may have a minimum order qty of 100 because that is the smallest quantity the vendor will sell. If NAV suggests that they buy 5, that is not possible to do, meaning the planner has to jump through hoops to address this (e.g., if he orders more, he then has to ignore messages on subsequent planning runs). The warning messages are not that helpful, and require additional clicking to review and analyse.
In another scenario that's quite common, people want to use lot-for-lot with a safety stock, but when they go below safety stock, they want to order a minimum qty - not just enough to take them back to the safety stock level.
In short, NAV should not be making suggestions that cannot be physically carried out, and should make it as easy as possible on the planner to do their job. We have fixed the NAV behaviour many times, as every client I've dealt with wants those modifiers respected. At the very least, this should be an option in the base product.