为什么在pyinstaller完成.exe之后，子进程的所有标准都被一次性打印到QTextBrower？

import sys
from PyQt5.QtWidgets import QApplication, QMainWindow, QTextBrowser
from PyQt5.QtCore import QProcess

class MainWindow(QMainWindow):
    def __init__(self):
        super().__init__()
        self.text_browser = QTextBrowser(self)
        self.setCentralWidget(self.text_browser)

        self.process = QProcess(self)
        self.process.readyReadStandardOutput.connect(self.update_output)
        self.process.start('your_executable.exe')

    def update_output(self):
        output = self.process.readAllStandardOutput().data().decode()
        self.text_browser.append(output)

if __name__ == '__main__':
    app = QApplication(sys.argv)
    window = MainWindow()
    window.show()
    sys.exit(app.exec_())