[GAMEPLAY] Rek'Sai tunnels forming but Rek'Sai not travelling through them.

Occasionally from time to time I will go to gank one of the side lanes as rek sai, and I usually like to cross over a wall when ganking to surprise the laner or avoid a ward, but sometimes when I go to tunnel, the tubes will form(I play with pool party reksai) but I wont go through it, and I cant wait for the cooldown to refresh to try again because the laner saw the tubes form, so the gank is a failure for what I think is an unfair reason. It has been happening to me more than usual latey, and I thought I had to bring it to attention. This only occurs when attempting to tunnel through an impassable terrain, and not when using it as a gap closer. It also does not happen all of the time, but I wold say it happens once every 5-6 times.