I am lucky enough to be able to work from home 95% of the time, but for the first 22 years of my career it wasn't so. I commuted from various locations on the edge of South East London to the The City (London's original Financial District, near Tower Bridge) every working day. A typical journey would take about 90 minutes each way, IF the trains were running on time. If they weren't, and that is unfortunately a regular occurrence, I could be experiencing 2-3 hours each way instead.
Property prices in London are insane, but even worse within walking distance of a train station. To even get to my local train station required a 15 minute drive from my house, and that's when I moved in; 10 years later from the same property that journey has become 30 minutes due to increase traffic levels. Once at the station, it costs about £8 a day to park in the station-side car park, however if you got there after 09:30, there are typically no free spaces, and with nowhere to park near the station either, you'd just have to give up *and drive back home*. I put myself down on a list to get a season ticket, which although still didn't guarantee me a parking space, did at least grant me access to the season ticket holders parking area before 09:30. It took three years of waiting before I finally got the season ticket. This season ticket for parking costs £1,200 a year.
Once on the train, unless I get a train that departs for London before 06:30, it will be packed solid with commuters, leaving squeezed standing room only. The journey is typically about 45 minutes (again if no delays), with the train stopping at many stations en-route, and even more people trying to squeeze on. For this enjoyable daily privilege, I pay about £180 a month on a travel pass.
The 90 minute commute comes from factoring in the unpredictable traffic for the drive to the station, plus waiting time at the station, plus the train journey, plus the walk to the office at the other end. And then I have to do it all again 8-10 hours later, to go home.
All because I wanted a nice house with a good garden for my family.
I have worked with many people whose commutes into London take longer (From Norwich, or York), but those people always have a seat with a table, Wifi, and food service, so it's way less of an ordeal.
London sucks. Don't work there if you don't have to.