OpenCV detecting hundreds of cars in footage with one car

Question

I've written a very simple script for detecting cars when given footage:

cap = cv.VideoCapture(1)
car_cascade = cv.CascadeClassifier('assets/cars.xml')


while True:
    ret, frame = cap.read()

    gray = cv.cvtColor(frame, cv.COLOR_BGR2GRAY)

    cars = car_cascade.detectMultiScale(gray, 1.1, 1)

    for (x, y, w, h) in cars:
        cv.rectangle(frame, (x, y), (x + w, y + h), (0, 0, 255), 2)


    # Display the resulting frame
    cv.imshow('frame', frame)
    if cv.waitKey(1) == ord('q'):
        break

# When everything done, release the capture
cap.release()
cv.destroyAllWindows()

I'm using the following file for my cars.xml: https://github.com/Aman-Preet-Singh-Gulati/Vehicle-count-detect/blob/main/Required%20Files/cars.xml. I've seen several projects that utilize this same Cascade file as well.

My problem is that when I spin up the video I see a screen like this, where hundreds of elements in the video are categorized as "cars" by the detectMultiScale function. I've been struggling to find anything on why this might be occuring.