Luis Suarez has been having a heck of a season pouring in 21 goals and counting for Liverpool. There is financial motivation for him to score. His FSG contract stipulated a wage increase from £80,000 to £100,000 per week on crossing a 20 goal threshold. Now, Suarez looks a player who needs little motivation but an additional £20,000 doesn't hurt, does it? 
Soccerblog has already discussed why wages at Arsenal should be incentivized, i.e., vary the wages according to performance and not some one size fits all formula. It is strange their CEO comes from a league known for it's high GINI co-efficient where rookies are paid about minimum wage while the DP's get millions of dollars. Their majority owner is the Walmart heir, an organization notorious for its intolerance of labor laws, vigorous anti-unionization drives, and non-existent worker benefits. Their employees are poorly compensated, work long arduous hours, and are hired and fired at will.
These two co-exist with a manager, who controls with an iron fist, all transfer spending and wages, resembling a socialist paradise; minimally performing players are kept on for years on high wages, while top performers leave as their wages hit a glass ceiling. The result, stagnation. Think about Lukas Podolski coming in for £90,000 per week (about the top Arsenal salary) and then playing about 10 minutes off the bench in that Spurs match, as he's done in a number of matches this season. What message do you think he's internalizing? The wage bill at Arsenal is a wage bill gone amok. It does absolutely nothing to improve this team, offers no motivation, yet every season it goes up, as it falls on the supporters to pay more every season. This is where the rubber hits the road.
The shift from Liverpool paying their players big basic wages with no, or very little, return (Alberto Aquilani, Joe Cole to name just two!!) is progressive and hopefully the club will benefit in the long term. Youngsters have come in and there are more to follow. If they progress the future of the club looks bright.
As far as Luis Suarez is concerned then he has without doubt earned his wage increase and if it serves as an inspiration to the youngsters then even better. His season has gone from strength to strength and he is now reaping the rewards. His style and his enthusiasm is a great example to everyone at the club, not just the youngsters.