The debt is real, and this is what it is made of
This course would be dishonest if it only ever told you what you do not owe. So here is the other side, and it is not small.
The Qur'an describes what a mother carried in bearing you and raising you, and the supplication of the one who reaches maturity, and the gratitude in it is not conditional on the parent having been easy.
Then the report where a man asks who is most deserving of his good companionship and is told his mother, three times, and then his father. Note carefully what the word is. It is companionship, suhba, which is care and closeness. It is not a ranking of whose orders you follow.
And the sound version of a sentence you have heard as a slogan. A man came wanting to go out and fight, was asked whether he had a mother, and was told to stay with her, for paradise is at her feet. In that setting, with that question. The floating slogan does a lot of damage in this topic and the sound narration is more specific and more useful than the slogan is.
Qur’an and Sunnah
وَوَصَّيۡنَا ٱلۡإِنسَٰنَ بِوَٰلِدَيۡهِ إِحۡسَٰنًاۖ حَمَلَتۡهُ أُمُّهُۥ كُرۡهࣰ ا وَوَضَعَتۡهُ كُرۡهࣰ اۖ وَحَمۡلُهُۥ وَفِصَٰلُهُۥ ثَلَٰثُونَ شَهۡرًاۚ حَتَّىٰٓ إِذَا بَلَغَ أَشُدَّهُۥ وَبَلَغَ أَرۡبَعِينَ سَنَةࣰ قَالَ رَبِّ أَوۡزِعۡنِيٓ أَنۡ أَشۡكُرَ نِعۡمَتَكَ ٱلَّتِيٓ أَنۡعَمۡتَ عَلَيَّ وَعَلَىٰ وَٰلِدَيَّ وَأَنۡ أَعۡمَلَ صَٰلِحࣰ ا تَرۡضَىٰهُ وَأَصۡلِحۡ لِي فِي ذُرِّيَّتِيٓۖ إِنِّي تُبۡتُ إِلَيۡكَ وَإِنِّي مِنَ ٱلۡمُسۡلِمِينَ
We have commanded man to be good to his parents: his mother struggled to carry him and struggled to give birth to him- his bearing and weaning took a full thirty months. When he has grown to manhood and reached the age of forty he [may] say, ‘Lord, help me to be truly grateful for Your favours to me and to my parents; help me to do good work that pleases You; make my offspring good. I turn to You; I am one of those who devote themselves to You.’
Qur’an 46:15
It was narrated from Mu'awiyah bin Jahimah As-Sulami, that Jahimah came to the Prophet (ﷺ) and said:"O Messenger of Allah! I want to go out and fight (in Jihad) and I have come to ask your advice." He said: "Do you have a mother?" He said: "Yes." He said: "Then stay with her, for Paradise is beneath her feet
Sunan an-Nasa'i 3104graded sound, albanifull report
Narrated Abu Huraira:A man came to Allah's Messenger (ﷺ) and said, "O Allah's Messenger (ﷺ)! Who is more entitled to be treated with the best companionship by me?" The Prophet (ﷺ) said, "Your mother." The man said. "Who is next?" The Prophet said, "Your mother." The man further said, "Who is next?" The Prophet (ﷺ) said, "Your mother." The man asked for the fourth time, "Who is next?" The Prophet (ﷺ) said, "Your father
Sahih al-Bukhari 5971graded sound, sahihaynfull report
Translation: M.A.S. Abdel Haleem, The Qur'an, Oxford University Press, 2004.