And when harm touches man, he invokes Us, lying on his side, or sitting or standing. But when We have removed his harm from him, he passes on as if he had never invoked Us for a harm that touched him! Thus it is made fair seeming to the wasteful that which they used to do (12)
Man remembers Allah at Times of Adversity and forgets Him at Times of Prosperity
Allah tells us about man and how he becomes annoyed and worried when he is touched with distress.
وَإِذَا مَسَّهُ الشَّرُّ فَذُو دُعَاءٍ عَرِيضٍ
(but when evil touches him, then he has recourse to long supplications.)[41:51]
Long supplications' also means many supplications. When man suffers adversity he becomes worried and anxious. So he supplicates more. He prays to Allah to lift and remove the adversity. He prays while standing, sitting or laying down. When Allah removes his adversity and lifts his distress, he turns away and becomes arrogant. He goes on as if nothing were wrong with him before.
مَرَّ كَأَن لَّمْ يَدْعُنَا إِلَىٰ ضُرٍّ مَّسَّهُ
(He passes on as if he had never invoked Us for a harm that touched him!)
Allah then criticized and condemned those who have these qualities or act this way, so He said:
كَذَٰلِكَ زُيِّنَ لِلْمُسْرِفِينَ مَا كَانُوا يَعْمَلُونَ
(Thus it is made fair seeming to the wasteful that which they used to do.)
But those on whom Allah has bestowed good guidance and support are an exception.
إِلَّا الَّذِينَ صَبَرُوا وَعَمِلُوا الصَّالِحَاتِ
(Except those who have patience believe and do righteous good deeds.)[11:11]
The Prophet ﷺ said:
عَجَبًا (لِأَمْرِ) الْمُؤْمِنِ لَا يَقْضِي اللهُ لَهُ قَضَاءً إِلَّا كَانَ خَيْرًا لَهُ، إِنْ أَصَابَتْهُ ضَرَّاءُ فَصَبَرَ كَانَ خَيْرًا لَهُ، وَإِنْ أَصَابَتْهُ سَرَّاءُ فَشَكَرَ كَانَ خَيْرًا لَهُ، وَلَيْسَ ذَلِكَ لِأَحَدٍ إِلَّا لِلْمُؤْمِنِ
(How wonderful is the case of a believer; there is good for him in everything and this is not the case with anyone except a believer. If prosperity attends him, he expresses gratitude to Allah, and that is good for him. And if adversity befalls him, he endures it patiently and that is also good for him.)