I've just been revisiting our 'transfers in' since 2021/22 when Paratici joined :
Most players are straight forward to assess - and its a

to say the player is acceptable quality (and in some cases even excellent quality)
2021/22
Gollini - Loan, but not convincing
Romero -

Sarr -

Royal -

(versatile RB/LB.CB)
Gil - Great dribbler, but physically not up to PL
Kulusevski -

Bentancur -
2022/23
Lenglet (loan) - Loan, not up to Spurs standard
Forster (free) -

Covered Lloris absence at end of last season well
Perisic (free) -

Decent option off bench for assists
Danjuma (loan) - Not really tried by Spurs ?
Porro -

Spence - Jury out, but could be a dud for Spurs ?
Udogie -

Bissouma -

Richarlison - Tricky to assess on first year(ish), but 5 goals in last month very acceptable
2023/24
Vicario -

Van Der Ven -

Maddison -

Johnson -

Solomon - Not played enough to assess
Phillips - Youngster to assess next season
Veliz - Youngster to assess next season
Werner - Too early to assess, but looks promising
Dragusin - Too early to assess, but looks promising
Summary
So that's 14 players with a

- a successful player transfer.
- Richarlison is difficult to assess. If he keeps up his recent 5 goal success I think he's probably another

- 3 loans in didn't really work (Gollini, Lenglet and Danjuma)
- Gil is not physically up to PL
- Spence - jury is out
- Solomon, Phillips and Veliz, Werner and Dragusin not assessed as they've not played enough or just arrived at Spurs
Conclusion
Other than 3 loans which didn't work, its only Spence and Gil who haven't really worked out but 14 players who have worked out (and sometimes outstandingly well), and maybe a 15th with Richarlison.
And another 5 players (youngsters or just arrived) who might still come good.
In general commercial acquisitions of businesses its said that less than 50% of acquisitions live up to pre-acquisition expectations.
So this is an astonishingly successful transfer record over last 3 years , with so many successes and very few failures (most of whom were on 'try before you buy' loans, so very limited financial impact).
We really are cooking !