@Buttersamuri Er... let me point out the key differences between the 5th trial and the 1st trial, both times Makoto's luck was actively used.
- The 5th trial was different from other trials, as the truth did not matter. Monokuma was going to kill someone, which was originally Kirigiri, and the true murder wasn't in the room. Makoto then took it upon himself to hide his key information that could have lead to Kirigiri's death. Monokuma knew this and got angry at Makoto when Makoto didn't say anything and kept questioning the trial. He then on the spot, switched the accused to Makoto.
In the 5th trial, the truth did not matter and it was set up by the master mind. Makoto's luck could only last minute save Makoto from that.
- However, the 1st trial is something people tend to over look when it comes to Makoto's luck. Before the murder happened, Makoto was put into the only room that had a broke bathroom doorknob. It wasn't intentional by anyone and Monokuma laughed at Makoto's misfortune. Later, Sayaka was murdered in Makoto's bathroom. They previously switched places because Sayaka was originally planned to pin her murder on Makoto.
Sayaka was murdered instead and the murderer thought he was in Sayaka's room, as Sayaka tricked him before hand, so he broke down the door. All the girls have locks in their bathrooms but the guy's didn't. The murderer couldn't open the door and thought it was lock when it was just difficult to open.
Long story short, the difficult-to-open doorknob was the key evidence to prove Makoto wasn't the murderer. Showing how Makoto's luck can protect Makoto by disguising itself as misfortune.