Never TO or TOO late? Which is correct?

“Never too late” is correct and “never to late” is incorrect. “Too” means something similar to  “excessively” while “to” is a preposition and part of an infinitive verb in English. 

I wish I could learn the guitar.

Never too late.

We need to use “too” because we want to show that he was gone “excessively soon”.  

Too vs To

To is a preposition and part of the infinitive of a verb.

I am driving to the cinema.

I need to drink water right now.

Too is an adverb that means “also” and “excessively”.

I miss you too.

I ate too much chocolate. 

Another way to say Never too late

If you want another way to say  Never too late” then you can say:

Never give up

Better late than never