How does the trailing stop loss work in practice?

[kittysoman2013]

I've been messing around with a trailing SL recently, on some of my trades it hit the SL and from what I can see, it then appears there is a huge liability should the price move back to being favourable. Does this happen because a lay bet is placed into the market once it hits the stop? Basically how does this work in practice? I've watched peters video on trailing stops and understand how it trails, but where does the bigger liability come from?

[Dallas]

If you use offset bet with greening the trailing stop will then green up to if its triggered and matched.
Otherwise you'll have all the loss on just that one selection which depending on the number of ticks used can be quite high