Allah knows best

Allah (s.w.t) says in the Holy Quran

... وَعَسَى أَن تَكْرَهُواْ شَيْئًا وَهُوَ خَيْرٌ لَّكُمْ... 

... وَعَسَى أَن تُحِبُّواْ شَيْئًا وَهُوَ شَرٌّ لَّكُمْ... 

... وَاللّهُ يَعْلَمُ وَأَنتُمْ لاَ تَعْلَمُونَ ﴿٢١٦﴾  

"And it may be that you dislike a thing which is good for you and that you like a thing which is bad for you. Allah knows but you do not know.” [AI-Baqarah, 2:216]

I think we have all been through a situation in life where we wondered why Allah didn't grant us that "thing" that was so simple and easy to acquire. Something that we were sure would do us good and not cause us any harm.

We tend to believe that we have a better knowledge and understanding of what is good and bad for us.

We feel disappointed and depressed when things done go our way, in the process we fail to realize that we really don't know what's best for us but surely Allah knows best !
                                                     
A lot of times we go back and reflect upon the things that didn't work out and the things that did and we realize that whatever happened , was for our good.
  
To explain it briefly,  we need to put our complete and unadulterated trust in Allah and accept the fact that ALLAH knows best, he is Al-‘Aleem (The All Knowing), Al-Khabeer (The All Aware),As-Samee’ (The All Hearing) and  (The All Seeing).

Having this blind trust makes it easy for us to face hardships and get closer to the Almighty.