The delay happens before the Wi-Fi login page
Joining a hotel or airport network usually takes two separate steps. First, your device connects to the local Wi-Fi equipment and gets basic network settings, such as an address it can use to communicate. Then it checks whether that connection actually reaches the open internet. The login page appears only after the device detects that access is restricted.
Phones and laptops make that check by trying to reach a small test page. On a network that requires sign-in, the request may be redirected to the venue’s welcome page instead. The device recognizes the unexpected response and offers to open a sign-in window, often called a captive portal: a web page that stands between you and full internet access.
Several small delays can stack up
The network may be busy, or it may take time to assign your device its settings. The device’s test request can also be slow to reach the network’s login system. If the test times out, the operating system may wait and try again before deciding that a portal is present. Then the login page itself still has to load.
A saved connection can make the sequence less obvious: your device may reconnect automatically, while the portal check runs in the background. And because the sign-in page is often hosted by the venue or a service provider rather than by the Wi-Fi access point beside you, a weak connection to that system can delay the screen even when the Wi-Fi icon appears.
The login window is a detection, not a Wi-Fi feature
The access point does not simply display a page as soon as your device joins. Your device has to recognize that internet access is being intercepted and decide to show the portal. That is why opening a browser yourself sometimes brings up the sign-in page sooner: it creates another request that the network can redirect. The wait is often the time it takes your device to establish that you are connected to Wi-Fi but not yet connected to the internet.
