It sounds counter-intuitive, but an interface can respond too fast.
When a site (like a booking portal) takes a long time to "gather all offers" for us, the perceived value is higher than when the result would be instantly there (even if technically possible). This is called "labor illusion".
Take this action
Think about parts in the user journey, when the user expects a lot of work going into a process. Slow down this process a bit and emphasise the value the user receives. But be careful. Slowing down a process too much will harm the user experience.