The scheduling of major sporting events like the Olympic Games and the FIFA World Cup in even-numbered years is not a universal rule, and these events have been held in both even and odd-numbered years throughout their history. The decision on the timing of these events is influenced by various factors, and the choice of year may differ for each event. Here are some reasons for events being held in even-numbered years:

1. Rotation: Many major sporting events, including the Olympic Games and the FIFA World Cup, follow a four-year cycle. The rotation allows different host cities and countries to prepare for and organize these massive events. When the cycle begins in an even-numbered year, subsequent editions also fall in even-numbered years.

2. Scheduling Considerations: Organizers consider various factors when scheduling these events, such as climate, logistics, and the availability of venues. Even-numbered years may be chosen to ensure favorable weather conditions for outdoor events.

3. Avoiding Clashes: Major sporting events often avoid scheduling conflicts with other significant events, including other sports tournaments and international competitions. This coordination may lead to events being held in even-numbered years to prevent overlap with major events in odd-numbered years.

4. Planning and Preparation: Hosting an event like the Olympic Games or the FIFA World Cup requires years of planning and preparation. Even-numbered years provide more time for host cities and countries to build or renovate facilities, infrastructure, and accommodations.

5. Tradition and Legacy: Some events have historical ties to certain years due to tradition or the legacy of past editions. For example, the modern Olympic Games have a tradition of being held every four years, starting in 1896, and this pattern has continued with some exceptions.

It's important to note that while some major sporting events may align with even-numbered years due to these considerations, there are also significant sporting competitions and tournaments that take place in odd-numbered years. The timing of events ultimately depends on the specific requirements and preferences of the organizers, host cities, and international sports governing bodies. The goal is to ensure the success, safety, and optimal conditions for athletes and spectators, regardless of whether the year is even or odd.