All items contain the following flags:
<flags count_in_cargo="0" count_in_hoarder="0" count_in_map="1" count_in_player="0" crafted="0" deloot="0"/>
What these do:
count_in_cargo - Count items stored in containers as part of Nominal Value (0=False, 1=True)
count_in_hoarder - tents, barrels, undeground stashes (0=False, 1=True)
count_in_map - Count items in map as part of Nominal Value (0=False, 1=True)
count_in_player - Count items stored in Player Inventory as part of Nominal Value (0=False, 1=True)
crafted - Is the item a crafted item (0=False, 1=True)
deloot - dynamic event loot objects - helicrashes in majority of cases only by default
(credits to https://trugaming.com/wiki/index.php/DayZ:_Other_Game_Info)
So in public servers each item has different settings to basically mean everything in cargo, hoarder, map and player all count to the overall nominal (the amount of that particular item allowed on the map). So once these nominals hit the max, they will stop spawning until another of that item despawns.
Some private/community servers stop this by setting the values to 0, meaning it doesn't count towards the nominal and will constantly keep spawning (until the max nominal is spawned). For example:
<type name="AK101">
<nominal>5</nominal>
<lifetime>28800</lifetime>
<restock>1800</restock>
<min>2</min>
<quantmin>-1</quantmin>
<quantmax>-1</quantmax>
<cost>100</cost>
<flags count_in_cargo="1" count_in_hoarder="1" count_in_map="1" count_in_player="0" crafted="0" deloot="0"/>
<category name="weapons"/>
<usage name="Military"/>
<value name="Tier4"/>
</type>
The default types XML markup for the AK101. As you see cargo and hoarder are both set to 1 on public/standard servers, this means if the AK101 is placed in a car, barrel, stash or something alike, it will count towards the amount on the map, so if you put 5 of them in a barrel, they stop spawning. Set these values to 0 and they will continue to spawn.
Private servers are so much better IMO because there's such a diverse range of playable servers catered for each individuals play style. Whether that be hardcore survival or max loot servers for PVP. Just gotta find the one you like the most 😉
Hope this helps, if you're confused about anything just ask 🙂