Your gear is maybe not optimum, and probably un-capped Hit.. Look with some reforge and theorycraft stuff, look what are doing your bot.
DPS is something really complicate even for the regular player. Dont think a bot will be better, because the day i will see a bot deals more damage than a player, i can tell him honnestly to suicide himself.
And the BOT is not doing multi-target dps, especially in Arcan mage. A lot of people know now after 8 years of WoW when u do Multi-target and spread DoT, is one of the greatest things to maximalize the DPS. But as i already said, even for the regular player is something complicate to keep eyes on 3 or more mobs in same times.
I will finish by saying something, A BOT is great to automatize the things who you have to do everyday, farming, leveling, grinding. But everybody here who know Honorbuddy for a good times, will answer u the same, there is 2 Option of Honorbuddy who are NEVER good or perfect, its BGBuddy and DungeonBuddy or LazyRaider.
The answer is simply, because there is some things where a smart human ( I mean the 20% of the mondial population who have more IQ than a cow. ) still better than a machine, an automatized system.
I can speak manny times about it, because i've been in the world top guilde and FR top guild for the first 6 years of the game. U have manny manny manny circonstance than a machine will NEVER can understand fast as a perfect player.
1. Do a perfect Circle of DPS.
2. Do your spell on your proc and the proc of raid members with a cancelaura.
3. When u have to straff something, u have to do it better and more fast than the DPS with who u raid or dungeons.
4. When u see around u somebody loose time, ( 1 sec or half a sec ) to moove " too " much, u can win dps by moving too but with the perfect move, thats means 2metters move less than the guys who make the mistake.
5. A perfect knowledge of the event, and the people who are playing around u..
Its 5 of the 20 i can announce here, who are not specially the topic, but i'll explain u that, to make u understand that bot will never be better than a player, never. And when i mean player, again, i mean the 10 % of population of brained people who stay on world of warcraft spread on all the realms of the games.
And if somebody have the balls to tell me i'm wrong, i can bet 100K Gold on everybody on this forums here, to make more DPS than me with a bot. ( Even without bot, but thats not so modest i agreed.)