Why is it difficult to predict a woman's ovulation period?

Predicting a woman's ovulation period can be challenging due to variability in menstrual cycles, which can be influenced by factors such as stress, illness, hormonal imbalances, and lifestyle changes. Additionally, cycles can differ significantly from month to month, making it hard to establish a consistent pattern. Ovulation can also occur later or earlier than expected, and not all women experience clear physical signs of ovulation, complicating the prediction further.