Is there a specific reason why numbers under 1001 are not used for items DB?

[GenTarkin]

I want to make custom items, Ive made some from 900 to 1000 already but wondering why it starts at 1001 , it works in EQ just fine summoning and them functioning part as a few quests I made.

is there any reason not to use these numbers? will the game have a fit or anything?

Thanks