Want to add anything new to the page? Well, at Amazon-scale, your little widget is going to have to go through some pretty intense design review and load testing, because at over 150 million page views per day, tiny time penalties can add up to significant capacity issues.
Amazon is also notorious for deep introspection of user behavior, so any little thing you want to add is going to have to go in to the big bin of factors that might influence a customer to "click the button" (or not). Data about your new feature will have to be integrated in to the models that are used to evaluate user behavior, or at a minimum, the group who handles that will have to sign off on not tracking the impact of your new feature on user behavior.
The whole concept of "the group that manages that" isn't unique to Amazon, but once you pass a certain size, you don't simply add features or new products without a involving lots of people. That is a challenge unique to Amazon-sized companies.
If you have a client asking for million dollar features on a 100k budget, the only solution is to find new clients. Some people are beyond help.
Clients and stakeholders alike will never cease the asking for more than you can reasonably deliver because they have absolutely no way of knowing how reasonable their request is. That is why pulling all nighters and heroics are so bad for developer / business relationships. They set a precedent for what is reasonable or possible.
If the client or stakeholder never really can have the data necessary to fairly judge whether you are "holding out" or not then the only thing you can do is build personal trust by doing what you say you will, not a damn thing more, not a damn thing less.
Hardware, software, anything really - there's probably an analog to this in most things.
Personally, what I run up against most often aren't questions about fulfilling the initial requests, but the aftermath of someone focusing on specific details to the exclusion of the bigger picture.
An organization spending a few million on software licenses, but nothing on staff / support being the most common example.
I feel like people in tech are particularly prone to this for whatever reason.
I'd wager a person will typically to sustain more criticism for a sub-optimal, but complete, functional implementation than a disjoint pile of fine-tuned components that doesn't add up to anything.
Can you provide an example to back up your claim?
Now of course none of this was impossible to do before, but the advent of all major browsers now supporting web sockets, and the existence of this framework and community which has already solved all of the hard parts of the implementation makes it actually feasible.
Twilio. Maybe Twilio is within the 5 year window too.
Mobile apps in general - the hardware infrastructure in peoples' pockets lets us do stuff with software that was not on most peoples' radars 5 years ago.
Hrmm... Amazon has dozens of people working and supporting just that one feature. You're trying to engage me to do an entire project. On a fixed budget. With a fixed time frame. And you've changed your mind 3 times in the last 3 weeks on key points.
Of course, yes, there are amazing things you can do with software that weren't remotely feasible even just 5 years ago. But there's always a moving target - the market leaders (Apple, Google, Amazon, etc) are constantly pushing the boundaries of what's considered 'normal', and most people have 0 idea of the real cost and effort involved in having the functionality come across as polished and error free as the big boys.