Can someone answer this for me? ^.^

Ty
It's an RNG based DPS class..

That and Scorch weaving is interesting.
Hot Streak, Impact and Combustion are all based around high crits to proc, and Ignite (which relies on high crits) is usually the second damage dealer below Fireball. Crit is a percentage, so you could crit or you might not, which accounts for discrepancy in dps.