Why generated class is identical even after random?

#include <iostream>
#include <vector>
#include <random>

using std::cout;
using std::cin;
using std::endl;
using std::ostream;

// Random value generator function
double randomize(const double &minVal, const double &maxVal){
	std::random_device rd;
	std::mt19937 genEngine(rd());
	std::uniform_real_distribution<double> distrib(minVal, maxVal);
	return distrib(genEngine);
}

class Warrior {
private:
	double _health;
	double _attack;

public:
	double HumanMaxAttrib = randomize(0.95,1.00) * 100;
    
   // Updated constructor (less flexibility when constructing)
    Warrior(){
        _health  = 100 * randomize(0.6,0.8);
        _attack  = 100 * randomize(0.6,0.8);;
    }

	// So that I could initialize with different strength.
	Warrior(const char &strength){
		if (strength == 'w'){
			_health   = HumanMaxAttrib * randomize(0.70,0.85);
			_attack  = HumanMaxAttrib * randomize(0.70,0.85);
		}

		if (strength == 'n'){
			_health   = HumanMaxAttrib * randomize(0.76,0.95);
			_attack  = HumanMaxAttrib * randomize(0.76,0.95);
		}

		if (strength == 's'){
			_health   = HumanMaxAttrib * randomize(0.86,1.00);
			_attack  = HumanMaxAttrib * randomize(0.86,1.00);
		}
	}

	double getHealth() const {return _health;}
	double getAttack() const {return _attack;}

	void setHealth (const double &health){_health = health;}
	void setAttack (const double &attack){_attack = attack;}

	ostream& toStream(ostream &os) const {
		cout<<"This is the Warrior attributes \n";
		cout<<"Health : "<<_health<<"\n";
		cout<<"Attack : "<<_attack<<"\n";
		return os;
	}
};

ostream& operator<<(ostream& os, const Warrior& v){
	return (v.toStream(os))  ;
}

constexpr char weak = 'w';
constexpr char normal = 'n';
constexpr char strong = 's';

int main(){

	Warrior war1(strong);
	cout<<war1;	// generate OK

	Warrior war2(normal);
	cout<<war2; // generate OK

	std::vector<Warrior> war3(3,Warrior(weak)); // generate identical. Why?
	for (auto i = 0; i < 3; i++) {
		cout<<war3[i];
	}

    // Using new constructor.
    std::vector<Human> itWorked(10);
    for (auto i = 0; i < 10; i++){     
    cout<<"Health: "<< itWorked[i].getHealth();
    cout<<"\nAttack: "<< itWorked[i].getAttack()<<endl<<endl;
    }

    return 0;
}