Shyvana is like a lighter

Early game wise, she makes really good amount of damage when her E, W, and Q are on but once she has used them all up, there's this long period of cooldown to where it's enough time for the enemy to kill you off.

During mid game, she's still the same.

During late game, she becomes rather amazing because of CD items to help her be constantly dealing damage as she tanks a little. But it's rare to even reach a late gaming phase for this kind of action to happen.

I'm not saying Shyvana is weak, but when she jungles around or ganks the enemy, the second her W and E goes on CD she can't finish the job and is very wide open. The only time she'll ever be able to finish the job is when the enemy is at least 40%HP but even with that if the enemy champion has a shield skill or a form of healing skill, it helps them survive from her ganks.

The enemy is WELL AWARE that her skills have this long period of CD in which she is super vulnerable.

In comparison to Udyr, he's able to finish the job quite efficiently because 1. he has stun, 2. his Q does damage overtime. Then you have his turtle stance that helps him eat up damage to give him more time to survive and be ready to go back into the fight.

I like to use Udyr as a comparison because he's quite similar to Shyvana except Udyr has more utility than Shyvana does. Shyvana needs the help of items to stick onto the enemy while Udyr has his stun and speed boost to do it all.

I guess in conclusion to this, I feel Shyvana lacks utility to help her finish the job and is way too reliant on items to do things for her.