How can you save resources when instantiaing driver?

I asked on my previous post about what was wrong in instantiating driver on set up method?

And here is the solution video on my YouTube channel (After 5 years of gap I finally added new video tutorial :))

The solution described on video tutorial uses following set up -

public class BaseClassOnDemandDriverSetup {

    private WebDriver driver;

    @BeforeMethod
    public void setupTest() {
        // Any other set up goes here
    }

    @AfterMethod
    public void teardown() {
        if (driver != null) {
            driver.quit();
        }
    }

    public WebDriver getDriver() {
        if(driver == null) {
            WebDriverManager.chromedriver().setup();
            driver = new ChromeDriver();
        }
        return driver;
    }
}