My Parents Are Very Impatient

I am very happy how I was raised by both of my parents, but the one thing I feel injustice about though is they are both very impatient, especially my dad, he can't stand patience to wait for anything and complaining most of the time, like he can't wait for a internet page to load or for the computer to access internet, says that cooking takes up to much time, how he can't wait for retirement that is in 3 years and keeps on complaining whenever the weather is bad, now I am saying all this because I was raised and told by both of my parents that it is good to learn patience and be patient and that you can't have everything suddenly, now I am used to being very patient with things in life but feel that unfairness that my parents, though taught me to be patient but they themselves aren't, and also with complaining, my dad tells me not to complain but he himself complains on almost anything and it is very annoying when he turns on his negativity, what is a good way to discuss about these matters with my parents?