All check boxes have labels, but not all check boxes use label tags to dis play their labels. This can cre ate click ing prob lems for users. Check boxes are small and hard to tar get. With out the label tags, users can’t click the check box labels to tick the check box. Instead, they’re forced to tar get and click the small check box itself, which can cause user frus tra tion, espe cially for motor-impaired users.
via Why Your Form Checkboxes Should Always Use Label Tags – UX Movement.