Hoarseness, vocal fatigue, and breathy quality are common symptoms of a voice problem (aka dysphonia). The reasons for these symptoms are variable. I work in conjunction with laryngologists (medical doctor who specialize in voice problems) to evaluate and treat people with voice problems.
Some of the voice problems we see:
Vocal fold nodules "vocal nodes"
Laryngitis
Vocal fold polyp
Vocal fold cyst
Vocal fold hemorrhage
Vocal fold scar
Vocal granuloma
Vocal fold cancer
Vocal fold paralysis
Muscle tension dysphonia
Vocal tremor
Spasmodic dysphonia
Vocal cord dysfunction (paradoxical vocal fold motion)
Chronic refractory cough
Irritable larynx syndrome
Presbylaryngis (aging voice)