The correct spelling of the phrase "wert habit of" is actually "were habit of". The reason for this spelling is due to the historical pronunciation of the word "were". In IPA phonetic transcription, it is pronounced as /wər/, where the "e" is a schwa sound. Over time, this sound merged with the word "was", leading to the modern-day irregular past tense of "was" and "were". Understanding the etymology and phonetics of words can help one to become a more proficient speller.