But assuming it's a genuine question:
There are many, many reasons. Just three off the top of my head as an example:
- They panic about the thought of bf in public in a society that fetishises breasts and often tells women "if you must bf in public for heaven's sake do it discreetly"
Just because society's attitude is wrong, or because you haven't experienced this (and you have iirc with relatives) doesn't make it any the less real.
- Their previous experience or the experience of family or friends tells them ff is easier than bf
Just because you or I see bf as the easy option doesn't mean everyone does. How many people have you heard say "when I switched to ff baby was more settled slept longer fed less often etc. etc."? And we live in a world where babies - and their mothers - are judged on how "good" they are!
- They are on medication that either is, or they are told is, incompatible with breastfeeding.
I think the former is pretty self explanatory really. And in the latter catagory - how often do you hear someone come on here and ask for a second opinion on something they (or their baby) has been prescribed being incompatible, and it turns out it isn't? Well, how many people take the Doctor's word at face value? Most people, really, and why wouldn't they?
And that's just three that I thought of from the top of my head. There are many, many more reasons for the 20% or so that don't initiate ("try") breastfeeding. And instead of starting OPs like this, the best thing to do is to try and remove some of those reasons (e.g. make bf in public easier, petition for laws like in Scotland etc.).
Also I think initiation (i.e. "trying") is a bit of a red herring. I think the problem of the 90% or so of women that stop in the first six weeks but didn't want to, is a bigger issue. Get them all breastfeeding as long as they want and others will hopefully follow, as the more bf people see, the more it becomes the "norm" and the more people will "try" it.