Since training with Pav, my indoor trainings have increased over the last two years. Below I share my insights on goals, completing and failing a workout indoors. Some principals go along with outdoor training as well.
Why indoors? It is a safe way of training, as there is no traffic. It is a perfect way to execute tough intervals without bothering other traffic or being annoyed by red lights. Third, it is much more efficient in terms of material. There is no chance on flat tires, and the time-consuming cleaning process after a winter ride is almost completely absent. However, make sure you clean your bike after every indoor ride as well. Especially the handlebars catch up a lot of sweat, even whilst using a towel!
Lastly, consistency beats instensity. Indoor training allows you to always show up as the weather is no longer an excuse. Time-comprised workouts offer a great value for the effort you put in. Consistency in this is still the champion of them all!
Feel free to add in the comments.
First and foremost:
Set a realist goal that you want to achieve (an ultra, GF, your first 100 miles etc). Consider the training (perhaps prescribed by Pav) as a building block towards that goal. Consider the goal as a big buy. All your trainingload is the money that goes into the bank account. As soon as you are at your event, you can get a lot from that bank account (when training has been executed consistently).
Second, a proper fan is half of the work. I have trained 1,5 winter with a cheap fan, resulting in many uncompleted workouts. Since riding with a good fan, 4 out of 5 workouts are completed succesfully. This used to be 2 out of 5. Bad weeks were even worse.
Three, chose your playlist wisely. You don’t want to be in a tough set and suddenly get a sad ballad on your ears. Perhaps some of us push harder when hearing Celine Dion, but most of us probably prefer hearing Kurt Cobain, in this respect.
Fourth, when doing Z2 on indoors, opt for cadence drills or small variation within Z2 (say ramp-ups from 60% to 75% and back). Monotonously riding Z2 on the same power for 5 hours indoors can be quite a torture. And be honest: do you really ride the same power in Z2 outside always? If you are into Zwift, a group ride or even a race might be a nice variation to the training schedule. Watching Netflix on easier workouts is also a great opportunity to stay up to date with your binge-watching friends 
Fifth, finish a workout as much as you can! All of us have those days where we do not feel entire fit. Or worse, we find out during the workout. Trust me, I have been here a lot.
Instead of stopping entirely in the midst of the workout (which can be the hardest part), it is better to have a break of a few minutes with easy or no pedalling. Try to come as close as you can to finish the workout. This way, you gain the most TSS. Even though not executed perfectly, you have still put in the work to your capabilities at that given moment.
Remember: your worst day in the arena is still better than your best day on the stand.
What you could do next time, is increasing or adding recovery parts in between the hardest parts. In my case it was: buy a proper fan!
Whatever you do, do not quit in the beginning or the middle! If you can no longer pedal near the end, that’s less of a problem. Do not make a habit out of it to quit though!
A last word on this: do not feel stressed or sad when you have not completed a workout because you felt worse than you had expected. Just show up next time, maybe adapt a bit by adding more rest (or let Pav have a look at it).
Sixth, as many workouts indoors are relatively short, some carbs in your drinks will be doing it. Unless discussed, there is no need to bring a lot of food. It costs you more (bars are not really cheap in the end) than it benefits you. Even on intense workouts, your body can cope with a lack of food for that relatively short time.
