The Zadok Yohanna deal from AIK to Brighton is a clean case study for two recruitment principles:
1. Clubs that make confident decisions from small sample sizes have an edge
~50% of Yohanna's total professional minutes (580') came in the last two months. Most clubs would prefer to wait for the sample to grow before making a move, but by the time it does, the price has already moved to reflect the larger sample size. Brighton (and other clubs, possibly because they trust Brighton's strategy) act earlier because they bet on their ability to analyze sparse information and make projections from a small sample size. The uniqueness of each player makes this principle a case-by-case application, but after watching Yohanna on Wyscout, this is a player where a 30 game sample size would only confirm - not deny - what the first 10 already show. Paying a fee that looks inflated relative to the player's experience and current level is rational when you're confident in a sample (or your analysis of that sample) that everyone else considers too thin.
2. There is lucrative business in being the middleman
AIK signed Yohanna out of Nigeria, gave him a platform in European football, and sold the proof of concept at a significant multiple. Scandinavia has become the connective tissue (middleman) between the West African market and bigger European leagues - sourcing the talent and letting buyers pay for the network connection rather than build those relationships themselves. This type of arrangement carries a better risk profile for the buyer and an enormous return for the seller, which is why it keeps repeating. The middleman's real product is their leveraged position within the supply chain that connects two markets who otherwise don't interact with each other.
Source where the information is this, decide before the market adjusts, and price on your own conviction.