Why is brushes with synthetic fillings better to use with water based paints?

Brushes with synthetic fillings are better for use with water-based paints because they are designed to resist water absorption, maintaining their shape and performance. Unlike natural bristles, synthetic fibers do not swell or become limp when wet, ensuring smooth application and a fine finish. Additionally, synthetic brushes are easier to clean, as they can be rinsed with water without losing their integrity, making them more durable and cost-effective for water-based projects.