From Dan Luu's excellent blog post on the value of in-house expertise [1]:
Another reason to have in-house expertise in various areas is that they easily pay for themselves, which is a special case of the generic argument that large companies should be larger than most people expect because tiny percentage gains are worth a large amount in absolute dollars. If, in the lifetime of the specialist team like the kernel team, a single person found something that persistently reduced TCO by 0.5%, that would pay for the team in perpetuity, and Twitter’s kernel team has found many such changes.
If removing a blinking cursor has a 1% chance to increase the booking rate by even 0.1%, , then it's worth it for AirBNB to pay an engineer to implement the change.
Another reason to have in-house expertise in various areas is that they easily pay for themselves, which is a special case of the generic argument that large companies should be larger than most people expect because tiny percentage gains are worth a large amount in absolute dollars. If, in the lifetime of the specialist team like the kernel team, a single person found something that persistently reduced TCO by 0.5%, that would pay for the team in perpetuity, and Twitter’s kernel team has found many such changes.
If removing a blinking cursor has a 1% chance to increase the booking rate by even 0.1%, , then it's worth it for AirBNB to pay an engineer to implement the change.
[1] https://danluu.com/in-house/