The real problem with Senna ADC is her SUPPORTS.
I don't know how many people are looking beyond impulsive win/ban/pick rate stats, but there's a glaring stat available on U.GG that speaks volumes as to what's actually wrong with Bot lane, and in fact..... many post 50% adcs:
https://u.gg/lol/duo-tier-list/
Duo tier calculates the win rates based upon a specific champion comp. Order by Win rate, and the top 6 responses are Senna as adc.
However..... Look at the supports she's teamed with:

And...... then you scan down the list for other Senna adc comps....... and you FINE NONE.
Somehow, Senna only has 6 tracked support combos, and none of them are
etc etc.
#They are Hard CC Supports, and primarily 2 specific supports:

Other than a Zyra/Jhin duo and an Ashe/Brand duo, Every single combo breaking a 55% win rate is either Senna or Nautilus or both.
Something else that should catch your eye: A lot of these duos are holding a 70% + Ban rate.
Part of that is attributable to Senna's own ban rate, but part of it is the fact people are banning these supports too.
33.2% Ban Rate
17.4% Ban Rate
43.2% Ban Rate
18.3% Ban Rate
9.8% Ban Rate
If you add up the pick rates for these supports, they make up literally 1/2 of Senna's active ADC games
Now...... Who are Senna's biggest counters?
are three of them.
In other words, Senna's in a unique position where all her winning duos are composed of her own counters, so that they can't counter her.
#But then you look down the list.... and Nautilus is the strongest duo for at least 12 adcs. Leona for 11.
#Has any of you considered that the primary difference between Support Senna and Adc Senna..... is the availability of a hard CC Support?
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