Answer:
Addition reactions are thermodynamically favored at low temperatures.
Step-by-step explanation:
Compared to substitutions or eliminations, addition reactions do not require to break as many bonds as them, as such, they do not require such a high input of energy (ie. temperature) in order to take place.
This is why if there's a high temperature, the reactions that require more energy -like substitutions or eliminations- will be more thermodinamically favored than the reactions that require less energy -like additions-, and viceversa.