Sorting by frequency/recency looks like the culprit. You often type 'for' and select forums.overclockers.co.uk, so the engine takes that into account and prioritizes that candidate, but you haven't done the same when typing 'forums', so it falls back on its normal sorting algorithm.

Seems that if a program has frequency/recency sorting, it'd best have an additional layer of intelligence such that it checks what results would've been returned by other substrings of your search term.

Or just key the frequency on the item clicked, not the term used to get there. If I use something a lot, it should generally take precedence over other possible matches.

Right! That makes sense.

On the other side it is rational if you think about it in abstract where there is no latency between screen and keyboard input. The likely reason you continued typing is that the prompt didn't include what you wanted.

I can see it as rational from a number of viewpoints - "When user types 'fo' they want to go here, 'foru' usually results in this, 'forum' has this result etc etc.

But I think all those other viewpoints lead to less desirable behaviour, for me. I'm not going to pretend it's universal because I don't have the research, but it pisses me off.