Yes thats right. Also we must put much more effort and concentration into our fard prayers as they are the most important prayers of all and will be judged and scrutinized the most.
If our fard prayers are lacking then our Sunnah and Nawafil prayers will be used to fill in the gaps.
That is why we must always try to pray all of our Sunnahs and Nawafil prayers.
If you need anymore help with anything at all then please do not hesitate to ask.