Aspirant , you have understand that there is services selection boards are rest of your personality too , there is no reference point when it comes to different individuals , something which is difficult for me could easy for you . Moreover they choose people who are fit for the armed forces , physically and mentally . You can't fit a square peg into a round whole , same goes for a candidate if he is fit for the services , getting recommended will be effortless for that individual but it might be a little difficult for those who need to change there personality. Moreover practice also plays an important role. Make sure you prepare well and leave no stone unturned.