By and large, Pokémon are inspired by real, actual animals that exist in our world. You’ve got your fire horses with Ponyta and Rapidash, bugs like Vespiquen and Wurmple, and aquatic life including Seaking and Sharpedo. Additionally, there are many that took a bit more creativity such as the Abra family or Mew and Mewtwo. They’re not obviously inspired by specific creatures, but they still look like they could be.
However, there are 721 Pokémon in total at the time of this writing. With such a massive cast of original creations, there are bound to be at least a handful that lack the charm and creativity present in so many others. The Pokémon included in this list – while they may have their own legitimate merits in-game – look like the designers closed their eyes and wandered around their houses until they tripped on something. Once they did they decided to slap a face on it and put it in the game.