I had a volunteer role to fulfill at Swindon Stations from 16:00 to 19:00 yesterday.  180 minutes. I am 35 minutes by public transport from home to Swindon Station - so 250 minutes?  I actually left home at 13:45 and got back at 21:05 - that's 440 minutes.  So what happened to the three extra hours?

The local bus calls at 13:44 at the timing point on the outskirts of Melksham as it runs into the toen ... so I left home at 13:45 to walk out to the nearest (to us) inbound bus stop ... picked up the bus from there at 13:52.  It should have dropped me off at Shurnhold (nearest stop for the station) at 13:59 but - although I ran the bell - the driver did not stop there, and stopped instead at George Ward Gardens (also a request stop).  His excuse of "I didn't hear the bell" doesn't wash - for I didnt ring again, and yet he stopped at George Ward. Me thinks he didn't realise there's a stop near the station.

Only 2 minutes from Shurnhold to George Ward Gardens, but 2 minutes at 30 m.p.h. is a mile ... we were a bit slower, but still didn't get back to the station until 14:15.  Fortunately, train and bus scheduled do not connect, so I was in good time for the 14:32 train.  If I hadn't been concerned to save energy for what I had lines up, I would have walked from home at around 14:00 ... as it was, using the bus turned out to be pretty pointless as I ended up walking the other way anyway - though a shorter distance.

But ... no ... thr final mile was not the biggest time looser, It was the lack of a train at the time I needed. Train service from Melksham to Swindon rose from un-usable to poor in 2013 ... and as it was, the train pulled in to Swindon just over an hour before my appointment.

Perfect world:
16:00 appointment at Swindon
15:55 train arrives
15:30 train from Melksham
15:25 arrive by bus at Melksham Station
15:15 join bus near home
15:10 leave house

Yesterday:
16:00 appointment at Swindon
14:59 train arrives
14:32 train from Melksham
14:15 arrive by bus at Melksham Station
14:01 get off bus at George Ward Gardens
13:52 joined bus near home
13:45 left home

Let's look at the return journey ... and allow for infrequent evening buses and walk home from Melksham Station

Perfect World:
19:00 finish in Swindon
19:10 train leaves
19:35 train arrives Melksham
20:00 walk into house

Yesterday using normal public transport:
19:00 finish in Swindon
20:45 train leaves Swindon
21:10 train arrived Melksham
21:35 walk into house

I managed to do marginally better - there is a daily National Express Coach from London to Frome that calls in Swindon and Melksham.
19:00 finish in Swindon
20:05 National Express Coach left Swindon Bus Station
20:55 Coach arrived Melksham (5 minutes early)
21:00 walked into house

Conclusion - the biggest time absorber is the very thin (infrequent) service, which is particularly painful where appointements / shifts are fixed, and not fixed conveniently. But there's an extra "gotcha" in there with poor intermediate connections.  Ironically, the poor connection from bus to train at Melksham proved to be my saviour, as I had time to get back to the station after the bus had failed to stop.

Overall?  If I drove, 15:00 from home ... 20:00 back ... 300 minutes. And that is what we are up against when we want to encourage people with cars to use public transport.  It's not just time - it's cost, convenience, quality of journey too ... but public transport needs to get that right too. If you had been stood with me yesteday evening in Swindon bus station - dark, cold, windy, wet, no information boards showing my service, you would realise that we haven't.  At present, all too many people buy a public transport journey out of necessity rather than because they have any choice.

On several newer busses, the bell is actuated on the first push, but subsequent passenger pushes for that same stop don't 'ring' in the cab.  The 'bus stop' sign is lit in the cab, but only the one audio ring occurs.

Yes, shout out/stand up if there's no sign of the driver pulling up 

Not applicable in this case. But apart from weekly shopping, I can't remember the last time I got on a bus without the Brompton. Gives me added flexibility.