Rizal became a hero because he's the one who passed the five criteria on selecting a national hero...with the selection of three person including Rizal,he's the one who had the one last of the criteria,the other two with the selection candidate to it were Graciano Lopez Jaena and Andres Bonifacio...
Here's the criteria...
1.,Isang Filipino
They're all filipino,so they all passed
2.,May matayog Na Pagmamahal Sa Bayan
They're also have it,so they passed
3.,May Madulang Kamatayan
Bonifacio and Rizal has it,not Lopez jaena for he died while sleeping after he drunk,he's a wine drinker...
4.,Yumao na
They're all dead
5.,May mahinahong Damdamin
In this one,Rizal were the one who only has it,for Bonifacio were in battle and in revolution while Rizal were still in Calmness
That's the reason why Rizal were the one who were selected for this title...
I hope it helped...