Does anyone know anything about gardening?

I don't think it's outlooks, it's more likely the free time.

It took me forever* to put the footings in for my kids Wendy House. The only reason I've been able to do it is because I'm now fortunate enough to have 2 free days a week when I can do these things. Once those became available it took me a day and a half.

Carving out the time to build a shed from scratch would mean after a long stressful week of work my OH would then have to spend the weekends doing all the childcare.

*edit ~7 months

A very condescending outlook there.

Building a shed from scratch, to the standard and looks of one you buy from any of the many companies out there, takes a lot of time. Time which, to a lot of people, is more valuable being spent elsewhere. Not everyone has the tools to make building a shed easy/quick/attractive.

A shed company has to buy the wood too. Just build your own shed surely? For a significantly lower cost you will end up with a significantly better building.

Not true. Shed companies will have access to trade accounts, with a much stronger buying power than a consumer. Consumers will be paying for the waste too. Unless you spend even more time at the planning stage to get your cut list totally perfect. Even the work bench I just bought. Simple thing made from 2x4's. I priced it up to build myself, but the chap on Etsy was selling it mostly constructed for 70% of the material costs I was able to calculate.

For my shed, it would have taken weeks to plan given that would need to be done around full time work and childcare. Then there's the actual construction, likely that would be months as I'd only have half days here and there on the odd weekends when we're not doing something else.

Instead, I got a fully constructed, good looking shed, erected in half a day, with no disruption to me whatsoever. The price of which was far less than the value of the days I would have spent trying to DIY. Plus, any fuck ups in construction are covered by the warranty. You can guarantee that there would be fuck ups at my own expense going the DIY route.

If someone wants to do it for themselves because they want the experience of the project, awesome, I fully support that. But it absolutely will not be significantly cheaper and/or better than buying.