Wikipedia:The Motivation of a Vandal

Some, however, go on to become persistent vandals.

With every warning the vandal receives for their vandalism, they feel a growing sense of self-satisfaction from the fact that their "work" has been acknowledged. This is a problem for the good editors, for by warning a vandal, they may be encouraging them to vandalize more to gain more attention.

After such a vandal has been blocked once, they may return later to vandalize again, but this time more stealthily. They still want recognition for their work, but take more care not to be blocked. They may change details in a page so that it affects the content of the page noticeably, but is not blatant vandalism. They may receive another warning, but they will not likely be immediately labeled as a vandal, which is exactly what they want.

Some of what is labeled as "vandalism" is in fact something more benign: "extremism" or "excess zeal". A person may read an article, see or imagine a glaring omission or flaw, and "fix" it. This often leads to long and protracted "edit wars", although in many cases, the "extremist" is the only editor who approves of his/her edit(s). The possibility exists that it is the previous editors who are "extreme", but this is unlikely for popular topics or articles with many editors.

Fortunately, such vandals are rare.

While most vandalism is done for attention, there are other possible motivations for vandalism:

While there is no big reason to defend these people, it may be important to note that this undesired transformation may be prevented by using more discussion and less force during dispute resolution. The only positive feature of this group is that they seldom vandalize for long, causing strong, unexpected but usually transient attacks.

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