Hadith: No one who enters Paradise would love to return to the life of this world even if he would be given everything that the world contains, except for the martyr. He will wish to return to the world and be killed ten more times on account of the honor that he will find

عن أنس رضي الله عنه : أن النبي صلى الله عليه وسلم قال: «مَا أحَدٌ يَدْخُل الجنَّة يُحِبُّ أن يَرجع إلى الدنيا وله ما على الأرض من شيء إلا الشَّهيد، يَتَمَنَّى أن يَرجع إلى الدنيا، فيُقْتَل عَشْر مَرَّاتٍ؛ لما يَرَى من الكَرَامة». وفي رواية: «لما يَرى من فَضْل الشَّهادة».
[صحيح] - [متفق عليه بروايتيه]

Anas (may Allah be pleased with him) narrated that the Prophet (may Allah's peace and blessings be upon him) said: "No one who has entered Paradise would love to return to the life of this world even if he would be given all that the world contains, except for the martyr. He will wish to return to the world and be killed ten more times on account of the honor that he will find." In another narration: "... on account of the merit of martyrdom that he will find."
[Authentic hadith] - [Narrated by Bukhari & Muslim]

Explanation

No one would desire to depart from Paradise after entering it and to return back to the life of this world even if he were given the whole earth with everything that it contains of treasures, luxuries, pleasures, huge palaces, and beautiful gardens, with the exception of the martyr. The martyr would love to return to this world ten more times so that each time he would fight in the cause of Allah and be martyred ten times instead of just once on account of the great honor and reward and bountiful blessings that are bestowed on him as a martyr after his death.