I keep seeing people complaining about how Infernape sucked and should be used less.
Although I have never used Infernape, it's movepool and stats aren't that horrible.
I would like to ask, why is Infernape do harshly criticized?
Infernape recievs heavy, heavy competition from both Keldeo and Terrakion, which are both Fighting-types in the base 108 tier as well. Simply put, Terrakion and Keldeo are more powerful than Infernape (129>>>>>104) and have better STAB's.
Keldeo: Secret Sword acts as a physical attack even though it runs off of special attack. This effectively gives Keldeo two STAB moves to abuse off a
fully invested base 129 attacking stat. Meanwhile Infernape's EV investment into its attacking stats is often split, so sometimes it doesn't even get past base 100 investment in either of its stats. Keldeo also has its STAB boosted by the omnipresent Rain, which makes it terrifying to face. Meanwhile Infernape has its STAB dampened in power. Sun is not common enough to really take advantage of Infernape's Fire-type STAB. So to retain that power, you have to run either sun of sand, but sand destroys ape because he relies on life orb. Also keldeo's stab water is incredibly useful for sand teams.
Terrakion: Coverage? Who needs coverage? Terrakion certainly does not when his STAB's alone cover the entirety of OU and when only a very small handful of Pokemon who are never in OU are the only ones to resist. Essentially all you need to run on Terrakion for its attacks are Stone Edge and Close Combat. This effecectively gives it 2 free moveslots to do whatever the hell it wants. Double boosting set (good luck Infernape pulling that off). Done. Hard hitting SR lead with Taunt? Done. Almost unwallable CB user because of its STAB's? Done. Choice Scarf user that can revenge all the game's top threats while still hitting hard (look at the scarf ape in QC)? Done.
There is also a lot of other minute stuff too. Keldeo and Terrakion are resistant to SR, so they can stay in the game longer and switch more often. Also they are much bulkier than Infernape. Keldeo's and Terrakion's decent bulk let's them play off resists quite well.
In my opinion, unless your Infernape has U-turn or Iron Fist Mach Punch on it, stick with Terrakion or Keldeo. Even on Sun teams, Terrakion and Infernape are a close call, especially their Scarf sets. Infernape's Fire STAB becomes really hard to manage, and it call pull off sweet momentum gains with U-turn. But Terrakion more ably checks the threats to Sun teams, especially Dragonite and Volcarona (Terrakion resists ESpeed and can use Rock Slide/resist volc handily if it gets to +2).
I remember when it was cool to criticize Infernape haters