I have Time Warner Cable as my cable provider. They have open WiFi hotspots throughout the city where I live. Typically, the hotspots will show up as fair (2 bars) or good (3 bars). I'll try to connect to the hotspot and what I see happen is that the signal instantly drops to one bar (poor) and doesn't connect. A few seconds later, the same wifi hotspot signal shows up again with the same signal level (2 or 3 bars). It might connect this time, but will remain connected as a poor signal meaning that the signal is too weak to reliably access a webpage or even stream music.
Other times, I happen to be in the right spot where the signal shows up as excellent (4 bars). Despite the signal apperance, I sometimes cannot get connected to the hotspot. It just won't connect at all and the phone will continue to remind me that WiFi is available, or what will happen is that I will look at the connection status and see that it's stuck on 'obtaining IP address' for several minutes. On my home network when I come in from outside, sometimes my own networks will just completely drop off from the phone. About 2-3 minutes later, they will come back.
I feel like there could be an issue with the phone because I've reported to Verizon support, calls with static on the line. Verizon determined there were absolutely no problems with the network at the time I reported this. Weak 4G signals that I've put in tickets for and Verizon network engineers have come back and reported that the area with the signal issues is a known low signal area. To me, a low signal area would seem to indicate that I should get at least some service and NOT no service at all or service at 1x that lasts 15-30 seconds standing still in the right place.
I attempted to resolve the WiFi connectivity issue with Time Warner and one of their employees dug up a forum post where someone with this exact phone mentioned problems with 4G service. So, Time Warner is apparently suggesting that weak 4G service is responsible for the WiFi connectivity issues. I'm looking at this from the standpoint that I've experienced a couple of other issues already and Verizon is essentially stating that the cause is not network related.
4G should have nothing to do with wifi. The hotspots you are trying to connect to may be crowded and the connection is so slow that it is timing out.