Very true, we are only able to achieve if we push hard and push through discomfort and do things that are hard. Be it with our body and building it or with achieving things in life.
And for normal people it doesn't matter how financially successful you are, you are always a dollar short or a day late...
It doesn't even have to be that uncomfortable. Most of us aren't curing cancer in our jobs, nor competing at the highest fitness levels for our hobbies - so how come we can't be even slightly uncomfortable? How come we can't stay a bit hungry, but we can overeat until we feel ill? We can't do some exercise, but can get a bad neck from sitting in front of a screen?
The excuses go on.