New boots may feel uncomfortable initially due to several reasons. The materials, especially if they are made of leather, can be stiff and need time to soften and mold to your feet. Additionally, the work boots insoles and footbeds might not have adjusted to your foot's contours yet. To ease the break-in process, it's advisable to wear the boots for short periods initially, gradually increasing the time as they become more comfortable. Choosing the right size and considering the specific requirements of your work can also impact the initial comfort of your boots.