Reasons why people don't like FTL's gameplay.
The scripting is such, that no matter how well you play, if you don't have ungodly amount of luck, you can't win.
Example. I could literally, write a thesis as to why people don't like this game, but I'll point out a few things that I notice on NORMAL mode.
#1. You get somewhere around 1/3 the scrap you would get, if you are not playing easy mode.
#2. Enemies spawn with Higher HP, tier II+ weapons from the start, and have 3 shields by the start of 4'th Sector.
#3 Coupled with reason #2, the store now charges much more for repairs than before. And since those cruisers you ran across had x2 5 burst lazers, you will be spending over 50% of your scrap on staying alive.
#4. Fuel becomes nearly impossible to find after Sector 6. So If you didn't stock up, you lost.
#5. The RNG element is so biased to failure, that I see more x3 shield, 15 health, dual rocket Auto pilot Scouts than I a random "you found ~blank~ giving you 1 missile and 22 scrap."
#6 Being Altruistic often rewards you by killing off one of your crew. Yay for punishing the good guys.
#7 In sector 7-8 in normal, the enemies all have F U L L Y upgraded shields, weapons, and 50% dodge rating. Good luck getting past that, even with a boarding party.
#8, Teleporting your boarding party onto a ship in sectors 5-8 results in losing them, as you get cascaded with missles and bombs, ensuring you that they cant be ported back. Or worse, are stuck on a F T L port away.
#9. Enemy ships have their weapons pre charged, ensuring that they get the first shot off, unless you have the augment, or a maxed Weapon's crew member.
#10, by Sector 6, every enemy npc you fight is maxed in fighting. I kid you not, I had 2 humans rush my ship, and start face tanking my 2 MAXED COMBAT rockmen. Only brought their 150 hp pool down faster than I could dps them.
Now before you start typing the fanboy mannerisms that I know I'll get. I'll say it up front, I love the game. I really do. But pretending that there is nothing wrong with the game, and saying "I Don't understand why some people don't like FTL's gameplay." Is just being a stubborn child who thinks that their enjoyment should take precedence over another's genuine grievances with the game's mechanics.
I guarantee that every single person reading this list has experienced a handful of these things on any given play through. Take it for what it is, constructive reasoning as to why people wouldn't like the gameplay. Its hyper RNG, its time consuming, and more to the point. If you lose, you get little more than a Antiquated score card and an option to quit or head back to the hanger.
I would prefer a giant middle finger myself, reminding me of the cheap mechanics that have soiled my good time by killing the crew i spent 4 hours working on.