Islam categorises all human actions into 5. The Fardh (compulsory), Sunnah (recommended), Halal (permissible), Makruh (offensive), Haram (forbidden). There used to be a time when if people were presented with a Makruh act, they’d say something like “It’s Makruh, I won’t do it” and if presented with a Sunnah, they say “It’s a Sunnah so I’ll do it”. People like me these days do it the other way round - “Ah, it’s just a Sunnah, we don’t have to do it.” and “It’s just Makruh, we don’t have to abstain from it.”
In this regard, here’s a reminder to all of us the importance of making the Sunnah a part of our lives.
The one who always leaves his sunnas will eventually be deprived of his fardh, such a person can never taste of the Divine beauty. [ Abdullah ibn Mubarak]
from the excellent Lessons of the day blog.