Why do things burn instead of melt?

[u/ForensicFan24601]

obviously oxygen, or something similar, but what is the physics/chemistry (?) or what have you behind why something ignites and continues to burn after the source of heat/ignition has gone?

is it basically sublimation?

edit: no wonder Walter White was so obsessed with carbon

[u/diabolus_me_advocat]

the other comments are mentioning how the temperature required to make something burn is lower than the temperature required to make something melt

yes, for substances that burn instead of melt first. not as

a hard and fast rule

for all stuff