Few questions about plot

Maybe I missed something.

1. So Fassbender f*cked up his job. So his middle man ordered to kill him off and send other killers. But why? To punish? He was obviously very skilled killer. Sometimes those assassins do fail for various reasons. He would do another job or could be told to finish this one. Why on earth killing him?

2. So they send killer to Dominicana. Tilda Swinton and Florida guy. So they had time to receive orders, fly from USA. Then come to his place. Did not find him, so they beat up his girlfriend. Who then somehow escaped. From two skilled assassins. All while bleeding out. Remember that Fassbender could barely take out Florida guy, so strong he was. But woman? Easy peasy. So she runs and those two killers are: "Oh well, he ain't home. What can we do?" Then they go to airport and fly home...

All while Fassbender was still flying from France. And keep in mind that he was ordered to be killed for failing mission. While THEM suffered zero consequences for failing their mission. Why weren't they killed too? Their f*ck up literally cost live of their middle man boss and rich employer was almost killed.

3. Fassy killing middle man boss was beyond stupid. What would he do if that secretary would not know names of those killers?

4. Fassy throwing his gear in trash cans was stupid. Any hobo could find it. Or police if they would check cameras and they see where "scooter guy" went. River was better place. But he mostly used trash cans.

5. Him walking in that Panama hat all the time was stupid. Eventually police would notice suspect who walks around in panama all the time and would be easy for them to single him out in cases and cctv.

6. He killed that poor taxi guy but then let rich guy live. While taxi guy was not a treat. But rich employer really was. While he thought: "Oh well I will threat him to kill him and he would be so scared that he will not come after me". But he never know people. Rich guy could be so scared that he would order everyone to take down that guy. He could threat like that taxi gut and poor secretary. They would keep quiet.

7. Tilda Swinton knew she would be dead. Could have made a splash in cafe instead of walking with him outside. Its not like she cared if he would kill everyone in that cafe. She had better chances fighting with him in public.

8. He should have killed rich guy and make it look like accident. That way no one would come after him. No one would knew. And its not like it was some mafia man. He was just some rich dude. He would die and no one would care to avenge him. Specially if it would look like accident. Fassy was too sloppy following him in gym. Cameras are everywhere these days.