Absolutely not! This phrase is banded around a lot when it comes to babies and sleep and it's a load of nonsense and does nothing but add pressure to an already sleep deprived parent doing their best!
For the first 4-5 months of a babies life they are still developing and may still require support getting to sleep. As their parent you are their safe space and they want to be close to you. So if you hold them, rock them, co sleep or feed them to sleep do not feel guilty for it. You are not doing anything wrong. You are simply responding to your child's wants ( or in reality doing whatever it takes to survive!)
As they get older they may want a bit more independence and to start trying to figure out how to fall asleep without you and so these methods of getting them to sleep may become less effective which is when you might find it takes longer for them to fall asleep or they may struggle to stay asleep.
It is easier to start changing these behaviours early on before your child becomes too reliant on a particular method of getting them to sleep but like any behaviour it is never too late to make changes and generally most behaviours can be changed within a few days so just because you rock your child to sleep right now does not mean that you will always have to do this. That "rod" is very much temporary!
If you do find yourself reliant on a sleep method that is no longer working for you or your child then get in touch to find out how I can support you to create new more effective habits.