QThreadPool lingers till the end of the app, for good or bad

threadpool-lingering.cpp

#include <QtCore>

class TurtleRunnable : public QRunnable
{
    void run() override {
        for (int i = 0; i < 15; ++i) {
            qDebug("Tick %i", i);
            QThread::sleep(1);
        }
    }
};

int main(int argc, char *argv[])
{
    QCoreApplication application(argc, argv);
    QThreadPool::globalInstance()->start(new TurtleRunnable);
    QTimer::singleShot(3000, [&application](){
        qDebug("I'd like to quit now");
        application.quit();
    });
    application.exec();
    qDebug("And done");
    return 0;
}