Incompetent

Villains who are more likely to accidentally foil their own plots than the heroes they're fighting against (unless if said heroes are the same) due to stupidity, cowardly behavior, weakness, equally more incompetent henchmen, egotism and/or arrogance on their part. Thus, they can be easily defeated and often hit the Scapegoat category because of this.

Incompetent villains mostly appear in comedies - where it is expected from the audience to see the main evil-doers or their henchmen fail miserably (such as Bebop & Rocksteady) - and most cartoons (e.g. many Looney Tunes villains), but can appear as well in serious or even mature stories - if this is the case, they are often Comic Reliefs. An example is Phil Cassidy. Evil organizations and corporations can also be labeled as incompetent, if most of their agents are themselves incompetent. The Team Rocket is a good example of this.

Incompetent villains can also be characters who have schemes that are ultimately stupid, pointless or do little to cause chaos. Sometimes their attempts at evil blow up in their faces by either causing them great harm or even aiding the heroes; thus, these villains are not really much of a threat but they can occasionally be dangerous or even intimidating. Additionally, characters who are stated or made out to be smart in the media they appear in, or even masterminds, such as Dr. Neo Cortex, Wile E. Coyote and Krang can still be classified as incompetent if they meet any of the previous qualifications, especially if their intelligence varies. However, some incompetent villains can actually be dangerous at times if they really put their minds to it. A good example of this is Zim.  Also, as mentioned, just because they are incompetent does not mean that they aren't smart. It is possible for villains to be good in a certain field, but still are too cowardly or arrogant to get the job done.

For obvious reasons, such villains are likely not successful, but in certain cases, they CAN still succeed in their goals, notably either if they have the help of much more frightening and competent villains, just with luck, or by learning from their own mistakes to become better.

Pure Evil villains will NEVER fall under Incompetent as they are capable of committing horrific acts that cause serious problems to everyone during stories, which actually makes them very competent and formidable.

Even if, in very rare cases, some Pure Evil villains are somewhat incompetent in other fields than villainy (e.g. Shou Tucker, Lord Djibril, Chaka, Joffrey Baratheon, Diodora Astaroth, Admiral Razorbeard and Toplofty and O'Bloat), they're still capable of committing horrific acts and thus, they should go under the Dimwits, Cowards, Weaklings and/or Arrogant categories instead.