As for the 2 year recommended lifespan of a racquet, that is nonsense for the most part and exactly what the company wants you and everyone else to believe. what a coincidence that they come out with a new line every – shock – 2 years!! Have you ever considered that a racquet may play even better as it gets worn? players who prefer a flexier, more muted frame will enjoy the feel of a racuet as it ages.

At the amateur level there are bundles of other factors that will influence the game many times over such things as ‘metal fatigue’

Your right, changes promotes motivation, but changes must be managed carefully so we don’t get bored along the way. More, it maybe a “cause-effect-cause” situation. I mean, , for example, one day you got a good performance, then you say “i deserve something new for that”, then you buy, lets say, a new racquet,or bag, then you got motivated again, and you got a new good performance, an so on.

I’m 46, a club level player, and i had the (right ? wrong ?) idea that racquets weighing under 280 grs. were not for me. I thought that these racquets promoted elbow injuries.
What was really happening is that i cannot deal well with 290 or 300 grs. Swing was not quick enough, i got tired, after 2 set i couldn’t serve … I have just changed to 275 grs and i feel better …

“C-H-A-N-G-E” as a suggestion and as a command.

Ex. A new rscquet cannot by itself make one a better player, but the idea, belief or ‘perception’ probably will make positive changes.

So, again I believe modern social psychology would affirm what you are contending: ‘make periodic changes’ these will give rise to the idea or belief that one is better at tennis … school, at relationships, etc.

EX. Three months ago I bought two new pairs of high tech tennis shoes; three weeks ago I bought a new, more modern racquet. People tell me that I am playing really well and ask, ‘Tim, have you changed any thing in your game?’

PRECEPTION IS REALITY!
Tim Garvey