Bitcoin closed 2025 with a yearly price decline, marking the first time it has fallen in the year following a halving event. This development has fueled debate over the validity of the "Bitcoin four-year cycle." Despite reaching a record high of $126,000 in October, Bitcoin's price has since dropped over 30%, leading to a weaker annual performance. Analysts are divided on the implications. Vivek Sen of Bitgrow Lab declared the four-year cycle "officially dead," citing Bitcoin's shift towards being influenced by macroeconomic factors rather than retail sentiment. Conversely, Markus Thielen of 10x Research argues the cycle persists but in a new form, not solely driven by halving events. The market remains split on Bitcoin's long-term cycle dynamics.