Here's why:
* Language is constantly evolving: Even languages that seem very regular can develop irregularities over time.
* Irregular verbs often come from older forms of the language: They reflect historical changes and can be remnants of grammatical structures that have since been simplified.
* "Irregular" is relative: What is considered an irregular verb in one language may be perfectly regular in another.
However, some languages are known for having fewer irregular verbs than others. Some examples include:
* Esperanto: A constructed language designed to be simple and regular. It has only a handful of irregular verbs.
* Mandarin Chinese: While Chinese has some irregular verbs, they are far fewer than in many other languages. The system for verb conjugation is generally quite regular.
* Turkish: Turkish has a fairly consistent pattern for conjugating verbs, with only a small number of exceptions.
It's important to remember that the concept of "irregular" is relative and depends on the language being considered.