Care to elaborate?I think the Rogue(Assassin) was built with the Poison Use to achieve the balance in the game for that class
Thanks for elaborating.Comparing the Assassin with the other classes – the Assassin is weakened without the use of poison and normally runs away from the battle because the assassin cannot go toe to toe with an equally matched level character (found out the hard way when my assassin was charmed by a demon and was forced to try to kill other party members, my assassin was on the ground in no time, even used the Cloak of Elvenkind to hide and attack from hiding, No Poison)
If the assassin had poison then the fighter would have been hurt more
The first 3 rounds of combat are normally all it takes to end a battle, and the 3 rounds are used to figure out the CR of a creature, the extra damage from poison increases the possible damage amount for one hit or two hits (2 weapons are poisoned)
No Poison and no companions:
First round – assassinate (Crit sneak attack) – flesh wound
Second round - weapon + nothing - very little damage
Third round - assassin is dead - or the assassin flees
Poison and no companions:
First round – assassinate (Crit sneak attack) - poison good damage (maybe poison condition or extra damage)
Second round - weapon + poison second weapon – good damage or victim has disadvantage to attack and saves
Third round - assassin wins - victim falls over dead
Do you have any evidence that supports that idea?I think the designers did take in the consideration of character balance and not group balance

(Dungeons & Dragons)
Rulebook featuring "high magic" options, including a host of new spells.