Wasn't sure where exactly to post this, so I thought this would've been the safe place to do it.
Okay, so we've all seen it or done it, or probably both. Your jungler wants to invade with the bot lane to either get an early kill, steal buff, or just slow their jungler down, and because of this, bot laners have formed a habit to guard the entry points before helping with the leash. For one reason or another, these things have happened.
Here's a story that happened just last week, and stuff like this is typically why I personally discourage the invade tactic.
So I was hiding in the brush like I usually do when I guard the spot, and sure enough, the enemy team was going for the invade (Jhin, Blitz and Kayn), and after we placed the wards down, as you would expect from any invades, all hell broke lose as we fought for kills and the buff. Our jungler (also Kayn) got the smite, I (Soraka) spammed my Q's, and our ADC (Tristana) got a double kill, and I Kill Secured the 3rd.
So obviously, the other team had a slow start. Their jungler was still level 1 and our ADC had 2 kills, which led to our yordle gunner snow balling. Long story short, she ended the game 28/1/4, in 21:42. The idea to invade slowly but surely...obliterated the other team into more pieces then a lego playset.
A smart, tactical play can result in a successful invade that significantly help your team's early game. Just remember....28/1/4. You prepared for that risk?